Fastener cartridge comprising a cutting member for releasing a tissue thickness compensator

ABSTRACT

A staple cartridge, or fastener cartridge, for a surgical stapler, or fastening instrument, wherein the staple cartridge includes a distally-located cutting blade arranged to cut a distal end portion of a layer, such as a tissue thickness compensator and/or a buttress material, for example, attached to the staple cartridge. The distally-located cutting blade can extend out of a distal cavity of the staple cartridge. The distally-located cutting blade can move in a direction that is perpendicular to a staple deck of the staple cartridge. The distally-located cutting blade can also move in any suitable direction relative to the staple deck.

CROSS REFERENCE TO RELATED APPLICATIONS

This non-provisional patent application is a continuation-in-partapplication under 35 U.S.C. §120 of U.S. patent application Ser. No.13/097,907, entitled COMPRESSIBLE STAPLE CARTRIDGE ASSEMBLY, filed onApr. 29, 2011, now U.S. Patent Publication No. 2012/0080338, which is acontinuation-in-part application under 35 U.S.C. §120 of U.S. patentapplication Ser. No. 12/894,360, entitled SURGICAL STAPLING INSTRUMENTWITH A VARIABLE STAPLE FORMING SYSTEM, filed on Sep. 30, 2010, now U.S.Patent Publication No. 2012/0080484, the entire disclosures of which arehereby incorporated by reference herein.

BACKGROUND

The present invention relates to surgical instruments and, in variousembodiments, to surgical cutting and stapling instruments and staplecartridges therefor that are designed to cut and staple tissue.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of this invention, and the manner ofattaining them, will become more apparent and the invention itself willbe better understood by reference to the following description ofembodiments of the invention taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a left front perspective view of a surgical stapling andsevering instrument with a handle portion including a link triggeredautomatic retraction and a ratcheting manual retraction mechanism;

FIG. 2 is a right aft perspective view of the surgical stapling andsevering instrument of FIG. 1 with a portion of an elongate shaft cutaway and a right half shell of a handle housing removed to expose anautomatic end-of-firing travel retraction mechanism and a manual firingretraction mechanism;

FIG. 3 is a right aft perspective disassembled view of the handleportion and an elongate shaft of the surgical stapling and severinginstrument of FIG. 1;

FIG. 4 is a right side view in elevation of the partially disassembledsurgical stapling and severing instrument of FIG. 1;

FIG. 5 is a right aft perspective view of the partially disassembledsurgical stapling and severing instrument of FIG. 1 with a closuremechanism closed and clamped and the side pawl firing mechanismcompleting a first stroke and with a manual retraction mechanism removedto expose a distal link of the linked rack that triggers automaticretraction of the firing mechanism;

FIG. 6 is a left side view in elevation of the partially disassembledsurgical stapling and severing instrument of FIG. 4 in an initial stateof end effector open and anti-backup mechanism engaged;

FIG. 7 is a left side detail in elevation of the disassembled surgicalstapling and severing instrument of FIG. 1 immediately after the distallink has actuated and locked forward the anti-backup release lever,allowing the linked rack to retract;

FIG. 8 is a right disassembled perspective view of the idler and aftgears and manual retraction lever and ratcheting pawl of a manualretraction mechanism of the surgical stapling and severing instrument ofFIG. 1;

FIG. 9 is a partially disassembled left side view in elevation of asurgical stapling and severing instrument of FIG. 1 with the anti-backupmechanism engaged to a fully fired linked rack that is disconnected froma combination tension/compression spring prior to actuation of themanual retraction lever of FIG. 8;

FIG. 10 is a partially disassembled left side view in elevation of thesurgical stapling and severing instrument of FIG. 9 with hidden portionsof the anti-backup release lever, aft gear, and manual firing releaselever shown in phantom;

FIG. 11 is a partially disassembled left side view in elevation of thesurgical stapling and severing instrument of FIG. 10 after actuation ofthe manual firing release lever has manually retracted the link rack;

FIG. 12 is a partially disassembled left side view in elevation of thesurgical stapling and severing instrument of FIG. 11 with the linkedrack omitted depicting the manual firing release lever disengaging theanti-backup mechanism;

FIG. 13 is a right side view in elevation of an alternative anti-backuprelease mechanism with the linked rack in a retracted position and theanti-backup release lever proximally positioned with the anti-backupplate engaged to the firing rod;

FIG. 14 is a right detail side view in elevation of the aft gear,automatic retraction cam wheel and distal-most link of FIG. 13;

FIG. 15 is a right side view in elevation of an automatic releasemechanism after a further firing stroke causes the automatic retractioncam wheel to distally slide and lock the anti-backup release lever,disengaging the anti-backup mechanism;

FIG. 16 is a left, front perspective view of an open staple applyingassembly with a right half portion of a replaceable staple cartridgeincluded in a staple channel;

FIG. 17 is an exploded perspective view of the staple applying assemblyof FIG. 16 with a complete replaceable staple cartridge and annonarticulating shaft configuration;

FIG. 18 is a perspective view of a plurality of staple driverspositionable within a cartridge body of a staple cartridge;

FIG. 19 is a perspective view of a two-piece knife and firing bar(“E-beam”) of the staple applying assembly of FIG. 16;

FIG. 20 is a perspective view of a wedge sled of a staple cartridge of astaple applying assembly;

FIG. 21 is a left side view in elevation taken in longitudinal crosssection along a centerline line 21-21 of the staple applying assembly ofFIG. 16;

FIG. 22 is a perspective view of the open staple applying assembly ofFIG. 16 without the replaceable staple cartridge and without a distalportion of a staple channel;

FIG. 23 is a front view in elevation taken in cross section along line23-23 of the staple applying assembly of FIG. 16 depicting internalstaple drivers of the staple cartridge and portions of the two-pieceknife and firing bar;

FIG. 24 is a left side view in elevation taken generally along thelongitudinal axis of line 24-24 of a closed staple applying assembly ofFIG. 16 to include center contact points between the two-piece knife andwedge sled but also laterally offset to show staples and staple driverswithin the staple cartridge;

FIG. 25 is a left side detail view in elevation of the staple applyingassembly of FIG. 24 with the two-piece knife retracted slightly more astypical for staple cartridge replacement;

FIG. 26 is a left side detail view in elevation of the staple applyingassembly of FIG. 25 with the two-piece knife beginning to fire,corresponding to the configuration depicted in FIG. 24;

FIG. 27 is a left side cross-sectional view in elevation of the closedstaple applying assembly of FIG. 24 after the two-piece knife and firingbar has distally fired;

FIG. 28 is a left side cross-sectional view in elevation of the closedstaple applying assembly of FIG. 27 after firing of the staple cartridgeand retraction of the two-piece knife;

FIG. 29 is a left side cross-sectional detail view in elevation of thestaple applying assembly of FIG. 28 with the two-piece knife allowed todrop into a lockout position;

FIG. 29A is a partial, perspective view of a jaw of an end effectorassembly with various elements removed therefrom according to variousembodiments of the present disclosure, depicting a firing assembly in anunfired position, and further depicting a sled engaged with a releasestop of an actuator;

FIG. 29B is a partial, perspective view of the jaw of FIG. 29A withvarious elements removed therefrom, depicting the firing assembly in apartially fired position, and further depicting the sled disengaged fromthe release stop of the actuator;

FIG. 30 is a perspective view of a surgical stapling instrumentincluding a shaft and a detachable end effector;

FIG. 31 is a partial perspective view of the shaft and the end effectorof the surgical stapling instrument of FIG. 30;

FIG. 32 is a partial perspective view of the end effector beingassembled to the shaft of the surgical stapling instrument of FIG. 30;

FIG. 33 is another partial perspective view of the end effector beingassembled to the shaft of the surgical stapling instrument of FIG. 30;

FIG. 34 is a partial cross-sectional elevational view illustrating theend effector uncoupled to the shaft of the surgical stapling instrumentof FIG. 30;

FIG. 35 is a partial cross-sectional elevational view illustrating theend effector coupled to the shaft of the surgical stapling instrument ofFIG. 30, and further illustrating a slide collar in an open, unlockedposition;

FIG. 36 is a partial cross-sectional elevational view illustrating theend effector coupled to the shaft of the surgical stapling instrument ofFIG. 30, and further illustrating the slide collar in a closed, lockedposition;

FIG. 37 is an exploded view of the end effector of FIG. 30 illustratedwith components removed;

FIG. 38 is an exploded view of the shaft of FIG. 30;

FIG. 39 is a longitudinal cross-sectional view of an anvil in a closedposition and a staple cartridge comprising a rigid support portion and acompressible tissue thickness compensator illustrated with staples beingmoved from an unfired position to a fired position during a firstsequence;

FIG. 40 is another cross-sectional view of the anvil and the staplecartridge of FIG. 39 illustrating the anvil in an open position afterthe firing sequence has been completed;

FIG. 41 is a partial detail view of the staple cartridge of FIG. 39illustrating the staples in an unfired position;

FIG. 42 is a cross-sectional elevational view of a staple cartridgecomprising a rigid support portion and a compressible tissue thicknesscompensator illustrating the staples in an unfired position;

FIG. 43 is a detail view of the staple cartridge of FIG. 42;

FIG. 44 is an elevational view of an anvil in an open position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition;

FIG. 45 is an elevational view of an anvil in a closed position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition and tissue captured between the anvil and the tissue thicknesscompensator;

FIG. 46 is a detail view of the anvil and staple cartridge of FIG. 45;

FIG. 47 is an elevational view of the anvil and staple cartridge of FIG.45 illustrating tissue having different thicknesses positioned betweenthe anvil and the staple cartridge;

FIG. 48 is a detail view of the anvil and staple cartridge of FIG. 45 asillustrated in FIG. 47;

FIG. 49 is a diagram illustrating a tissue thickness compensator whichis compensating for different tissue thickness captured within differentstaples;

FIG. 50 is a diagram illustrating a tissue thickness compensatorapplying a compressive pressure to one or more vessels that have beentransected by a staple line;

FIG. 51 is a diagram illustrating tissue captured within a staple;

FIG. 52 is a diagram illustrating thick tissue and a tissue thicknesscompensator captured within a staple;

FIG. 53 is a diagram illustrating thin tissue and a tissue thicknesscompensator captured within a staple;

FIG. 54 is a diagram illustrating tissue having an intermediatethickness and a tissue thickness compensator captured within a staple;

FIG. 55 is a partial cross-sectional view of an end effector of asurgical stapling instrument in accordance with at least one embodiment;

FIG. 56 is a partial cross-sectional view of an end effector inaccordance with at least one alternative embodiment;

FIG. 57 is a partial cross-sectional view of an end effector inaccordance with another alternative embodiment;

FIG. 58 is a partial cross-sectional view of an end effector illustratedin a flexed condition;

FIG. 59 is a partial cross-sectional view of the end effector of FIG. 58in a released condition;

FIG. 60 is a cross-sectional perspective view of a staple cartridgecomprising lateral retention members configured to hold a tissuethickness compensator to a support portion;

FIG. 61 is a cross-sectional view of the staple cartridge of FIG. 60being utilized to staple tissue;

FIG. 62 is a perspective view of a staple cartridge including acartridge body and a tissue thickness compensator attached to thecartridge body by a plurality of firable attachment members;

FIG. 63 is an exploded view of the staple cartridge of FIG. 62;

FIG. 64 is an elevational view of the staple cartridge of FIG. 62;

FIG. 65 is a cross-sectional view of the staple cartridge of FIG. 62taken along a cross-sectional line in FIG. 64 illustrating the firableattachment members in an unfired position;

FIG. 66 is a cross-sectional view of the staple cartridge of FIG. 62taken along the cross-sectional line in FIG. 64 illustrating the firableattachment members in a fired, broken, position;

FIG. 67 is a perspective view of a tissue thickness compensator;

FIG. 68 is a perspective view of the tissue thickness compensator ofFIG. 167 being assembled to a staple cartridge;

FIG. 69 is an exploded view of the tissue thickness compensator and thestaple cartridge of FIG. 68;

FIG. 70 is a detail view of a proximal end of a tissue thicknesscompensator;

FIG. 71 is a partial elevational view of the tissue thicknesscompensator of FIG. 70 assembled to a staple cartridge;

FIG. 72 is a plan view of the tissue thickness compensator and staplecartridge of FIG. 71;

FIG. 73 is a front view of a mount for holding a tissue thicknesscompensator to a staple cartridge;

FIG. 74 is a side view of the mount of FIG. 73;

FIG. 75 is a rear view of the mount of FIG. 73;

FIG. 76 is a bottom view of the mount of FIG. 73;

FIG. 77 is a partial cross-sectional view of a staple cartridgeincluding a retention pin configured to releasably hold a tissuethickness compensator to a cartridge body of the staple cartridge;

FIG. 77A is a partial cross-sectional perspective view of the staplecartridge of FIG. 77 with portions thereof removed for the purposes ofillustration;

FIG. 78 is a partial cross-sectional view of the staple cartridge ofFIG. 77 illustrating the retention pin in a defeated condition;

FIG. 79 is a partial cross-sectional perspective view of the staplecartridge of FIG. 77 also illustrating the retention pin in a defeatedcondition;

FIG. 80 is a partial cross-sectional view of a staple cartridgeincluding a clamp configured to releasably hold a tissue thicknesscompensator to a cartridge body illustrating the clamp in a closedcondition;

FIG. 81 is a partial cross-sectional view of the staple cartridge ofFIG. 80 illustrating the clamp in an open condition;

FIG. 81A is a perspective view of a staple cartridge with a layer, suchas a tissue thickness compensator and/or a buttress material, arrangedthereon, wherein the staple cartridge is arranged relative to an endeffector cutting blade, and wherein remaining portions of the endeffector are removed for purposes of illustration;

FIG. 82 is a cross-sectional plan view of the staple cartridge of FIG.81A, showing a cutting blade for severing the distal end of the layerarranged in a distal cavity in the staple cartridge, wherein the cuttingblade is undeployed, and wherein staples are omitted for purposes ofclarity;

FIG. 83 is a cross-sectional plan view of the staple cartridge of FIG.81A, wherein the cutting blade for severing the distal end of the layeris deployed, and wherein staples are omitted for purposes of clarity;

FIG. 84 is a perspective view of a jaw of an end effector assemblyaccording to various embodiments of the present disclosure, depicting atissue thickness compensator secured to a cartridge body by a proximalconnector and by a distal connector, and further depicting a firingassembly in an unfired position;

FIG. 85A is a partial, plan view of the jaw of FIG. 84, depicting theactuator in a pre-actuated position;

FIG. 85B is a partial, plan view of the jaw of FIG. 84, depicting theactuator in an actuated position;

FIG. 85C is a detail view of the jaw of FIG. 85B;

FIG. 85D is an elevation view of the jaw of FIG. 84, depicting theactuator in the actuated position, and further depicting the proximaland distal connectors broken;

FIG. 86 is a partial, elevation view of the jaw of FIG. 84 with variouselements removed therefrom, depicting a sled of the cartridge bodyengaged with a tab of the actuator of FIG. 85A;

FIG. 87 is a partial, elevation view of the jaw of FIG. 84 with variouselements removed therefrom, depicting the sled of the cartridge bodydisengaged from the tab of the actuator;

FIG. 87A is a partial, plan view of a jaw of an end effector assemblyaccording to various embodiments of the present disclosure, depicting afiring bar of a firing assembly against a release stop of an actuator;

FIG. 87B is a partial, plan view of the jaw of FIG. 87A, depicting thefiring bar of the firing assembly extending through the release stop ofthe actuator;

FIG. 88 is a perspective view of a jaw of an end effector assemblyaccording to various embodiments of the present disclosure, depicting atissue thickness compensator secured to a cartridge body, and furtherdepicting a firing assembly in an unfired position;

FIG. 89 is a partial, elevation view of the jaw of FIG. 88 with variouselements shown in transparency, depicting an actuator extending throughthe jaw, and further depicting the firing assembly in an unfiredposition;

FIG. 90 is a partial cross-sectional view of a staple cartridge whichincludes a retention pin configured to releasably hold a tissuethickness compensator to a cartridge body illustrating the retention pinin an activated condition;

FIG. 91 is a partial cross-sectional view of the staple cartridge ofFIG. 90 illustrating the retention pin in a deactivated condition;

FIG. 92 is a perspective view of an actuator of the staple cartridge ofFIG. 90 which is configured to deactivate the retention pin;

FIG. 93A is a perspective view of a fastener cartridge assembly of anend effector assembly according to various embodiments of the presentdisclosure, depicting a tissue thickness compensator released from acartridge body of the fastener cartridge assembly;

FIG. 93B is a perspective view of the fastener cartridge assembly ofFIG. 93A, depicting the tissue thickness compensator secured to thecartridge body of the staple cartridge assembly;

FIG. 93C is an elevational view of the fastener cartridge assembly ofFIG. 93A with various elements removed therefrom, depicting a firingassembly in a pre-fired position;

FIG. 93D is an elevational view of the fastener cartridge assembly ofFIG. 93A with various elements removed therefrom, depicting the firingassembly in a partially-fired position;

FIG. 94 is a partial, perspective view of a fastener cartridge assemblyof an end effector assembly according to various embodiments of thepresent disclosure, depicting a tissue thickness compensator releasedfrom a cartridge body of the fastener cartridge assembly;

FIG. 95 is a partial, perspective view of a fastener cartridge assemblyof an end effector assembly according to various embodiments of thepresent disclosure, depicting a tissue thickness compensator releasedfrom a cartridge body of the fastener cartridge assembly;

FIG. 96 is a partial, cross-sectional view of the fastener cartridgeassembly of FIG. 95, depicting a mount of the tissue thicknesscompensator held in a bridge of the cartridge body;

FIG. 97 is a perspective view of a fastener cartridge assembly of an endeffector assembly according to various embodiments of the presentdisclosure, depicting a tissue thickness compensator released from acartridge body of the fastener cartridge assembly;

FIG. 98 is a perspective view of the fastener cartridge assembly of FIG.97, depicting the tissue thickness compensator secured to the cartridgebody of the fastener cartridge assembly;

FIG. 99 is an elevational, cross-sectional view of the end effectorassembly of FIG. 97, depicting the tissue thickness compensator securedto the cartridge body of the fastener cartridge assembly, and furtherdepicting the end effector in an unclamped position;

FIG. 100 is an elevational, cross-sectional view of the end effectorassembly of FIG. 97, depicting the tissue thickness compensatorunsecured to the cartridge body of the fastener cartridge assembly, andfurther depicting the end effector assembly in a clamped position;

FIG. 101 is a perspective view of a staple cartridge applicator assemblycomprising an upper tissue thickness compensator including a pluralityof retention features extending therefrom and a staple cartridgecomprising a lower tissue thickness compensator;

FIG. 102 is an elevational view of the staple cartridge applicatorassembly of FIG. 101 positioned within a staple cartridge channel and ananvil being closed onto the staple cartridge applicator assembly;

FIG. 103 is an elevational view of the anvil of FIG. 102 in a re-openedposition and the staple cartridge applicator of FIG. 101 being removedfrom the end effector;

FIG. 104 is a cross-sectional view of tissue positioned intermediate theupper tissue thickness compensator and the lower tissue thicknesscompensator of FIG. 101;

FIG. 105 is a cross-sectional view illustrating the upper tissuethickness compensator and the lower tissue thickness compensator stapledto the tissue and severed by a cutting member;

FIG. 106 is a perspective view of staple cartridge applicator assemblycomprising an upper tissue thickness compensator configured to beattached to an anvil in accordance with at least one embodiment;

FIG. 106A is an elevational view of the staple cartridge applicatorassembly of FIG. 106 positioned within a staple cartridge channel and ananvil being moved toward the upper tissue thickness compensator;

FIG. 106B illustrates the staple cartridge applicator of FIG. 106 beingremoved from the end effector after the upper tissue thicknesscompensator has been engaged with the anvil;

FIG. 107 is a cross-sectional end view of the anvil being moved towardthe upper tissue thickness compensator of FIG. 106;

FIG. 108 is a cross-sectional end view of the anvil engaged with theupper tissue thickness compensator;

FIG. 109 is a perspective view of a staple cartridge having a piece ofbuttress material releasably retained thereto in accordance with onenon-limiting embodiment of the present invention;

FIG. 110 is an exploded, perspective view of the staple cartridge andthe piece of buttress material of FIG. 109, wherein the piece ofbuttress material includes a plurality of members extending therefrom;

FIG. 111 is a cross-sectional view taken along line 111-111 in FIG. 109illustrating the members of FIG. 110 engaged with staple cavities inaccordance with one non-limiting embodiment of the present invention;

FIG. 112 is a cross-sectional view of a piece of buttress materialincluding members engaged with staple cavities of a staple cartridge inaccordance with one non-limiting embodiment of the present invention;

FIG. 113 is an exploded view of FIG. 112 illustrating the membersseparated from the staple cavities of the staple cartridge in accordancewith one non-limiting embodiment of the present invention;

FIG. 114 is a partial, perspective view of a support portion of a staplecartridge comprising detachable and/or displaceable staple leg guides;

FIG. 115 is a partial, cross-sectional view of the staple cartridge ofFIG. 114 illustrating staples being deployed from the staple cartridge;

FIG. 116 is a detail view of the cross-sectional view of FIG. 114 afterthe staple cartridge has been fired;

FIG. 117 is a partial, perspective view of a cartridge body, a shell,and a tissue thickness compensator according to various embodiments tothe present disclosure, depicting projections extending from thecartridge body;

FIG. 118 is a partial, perspective view of a cartridge body, a shell,and a tissue thickness compensator according to various embodiments ofthe present disclosure, depicting projections extending from the shell;

FIG. 119 is a partial, cross-sectional view of an end effector assemblyaccording to various embodiments of the present disclosure, depicting astaple positioned in a staple cavity of a cartridge body of the endeffector assembly, and further depicting the staple in an unformedconfiguration;

FIG. 120 is a partial, cross-sectional view of the end effector assemblyof FIG. 119, depicting the staple ejected from the staple cavity, andfurther depicting the staple in a formed configuration;

FIG. 121 is perspective view of a staple and a lock according to variousembodiments of the present disclosure, depicting the lock in a lockedconfiguration;

FIG. 122 is a perspective view of the staple and the lock of FIG. 121,depicting the lock in the locked configuration;

FIG. 123 is a perspective view of the staple and the lock of FIG. 121,depicting the lock in a pre-fired position in a staple cavity, andfurther depicting the lock in the locked configuration;

FIG. 124 is a perspective view of the staple and lock of FIG. 121,depicting the lock in a fired position in the staple cavity, and furtherdepicting the lock in an unlocked configuration;

FIG. 125 is a perspective view of a fastener cartridge assembly of anend effector assembly according to various embodiments to the presentdisclosure, depicting locks extending from lock cavities in a cartridgebody of the fastener cartridge assembly;

FIG. 126 is a cross-sectional view of a lock of FIG. 125, depicting thelock in an unlocked configuration and a connector unsecured to the lock;

FIG. 126A is a partial, cross-sectional view of the fastener cartridgeassembly of FIG. 125, depicting the cartridge body, a connector, atissue thickness compensator, and a lock in a partially assembledposition;

FIG. 127 is a partial, cross-sectional view of the fastener cartridgeassembly of FIG. 125, depicting the lock in a locked configuration,depicting an anvil in a clamped position, and depicting a driver key inan unfired position;

FIG. 128 is a partial, cross-sectional view of the fastener cartridgeassembly of FIG. 125, depicting the lock in a locked configuration,depicting the anvil in the clamped position, and further depicting thedriver key in a partially-fired position;

FIG. 129 is a partial, cross-sectional view of the fastener cartridgeassembly of FIG. 125, depicting the lock in the unlocked configuration,depicting the anvil in the clamped position, and further depicting thedriver key in the fired position;

FIG. 130 is a cross-sectional view of an end effector of illustrating afiring member in a partially-fired position;

FIG. 131 is a cross-sectional view of the end effector of FIG. 130illustrating the support portion being moved away from thepartially-implanted tissue thickness compensator;

FIG. 132 is partial cut-away view of a staple cartridge comprisingstaple drivers having different heights in accordance with at least oneembodiment;

FIG. 133 is a diagram illustrating the staple drivers of FIG. 132 andstaples having different unfired heights supported thereon;

FIG. 134 is a cross-sectional view of a staple cartridge comprising atissue thickness compensator and a support portion in accordance with atleast one embodiment;

FIG. 135 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired position;

FIG. 136 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 137 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 138 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 139 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 140 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 141 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 142 is a detail view of a region surrounding a tip of the staple ofFIG. 141;

FIG. 143 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 144 is a detail view of a region surrounding a tip of the staple ofFIG. 143;

FIG. 145 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 146 is a perspective view of a staple guide layer and a pluralityof staples in an unfired position in accordance with at least onealternative embodiment;

FIG. 147 is an exploded view of a tissue thickness compensator and astaple cartridge body;

FIG. 148 is an elevational view of a disposable loading unit including apivotable jaw configured to support a staple cartridge;

FIG. 149 is a perspective view of a tissue thickness compensatorapplicator positioned within an effector of a disposable loading unit;

FIG. 150 is a top perspective view of the tissue thickness compensatorapplicator of FIG. 149;

FIG. 151 is a bottom perspective view of the tissue thicknesscompensator applicator of FIG. 149;

FIG. 152 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising staple drivers having different heightsand a contoured deck surface in accordance with at least one embodiment;

FIG. 153 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising staple drivers having different heightsand a stepped deck surface in accordance with at least one embodiment;

FIG. 154 is a diagram illustrating a tissue thickness compensatorcomprising a varying thickness, staple drivers having different heights,and staples having different unformed heights;

FIG. 155 is a diagram illustrating the staples and the tissue thicknesscompensator of FIG. 154 implanted to tissue;

FIG. 156 is a partial cross-sectional view of a tissue thicknesscompensator attached to a staple cartridge body;

FIG. 157 is a partial cross-sectional view of a the tissue thicknesscompensator and the staple cartridge body of FIG. 156;

FIG. 158 is a partial exploded view of the tissue thickness compensatorof FIG. 156;

FIG. 159 is a partial exploded view of a tissue thickness compensator, astaple cartridge body, and a firing member;

FIG. 160 is a partial elevational view of the embodiment of FIG. 159;

FIG. 161 is a bottom view of a staple cartridge;

FIG. 162 is a detail bottom view of the staple cartridge of FIG. 161;

FIG. 163 is an exploded view of a staple cartridge illustrating a stapledriver arrangement;

FIG. 164 is a perspective view of an embodiment of a retainer attachedto a staple cartridge and with a layer, such as a tissue thicknesscompensator, arranged intermediate the retainer and the staplecartridge, wherein the retainer, layer, and staple cartridge arearranged relative to a surgical stapler, and wherein a staple cartridgechannel is removed for purposes of illustration;

FIG. 165 is a perspective view of the retainer of FIG. 164;

FIG. 166 is a plan view of the retainer, layer, and staple cartridge ofFIG. 164;

FIG. 167 is a cross-sectional view of the retainer, layer, and staplecartridge of FIG. 164, wherein tips of staples extend from staplecavities in the staple cartridge and into the layer;

FIG. 168 is a perspective view of an embodiment of a retainer, whereinthe retainer includes moveable cam portions and locking tabs;

FIG. 169 is a perspective view of the retainer of FIG. 168 attached to astaple cartridge, wherein the staple cartridge and retainer arepositioned for insertion into a staple cartridge channel of an endeffector of a surgical stapler;

FIG. 170 is a plan view of the retainer of FIG. 168 positioned, but notfully inserted, into a cartridge channel of the end effector of thesurgical stapler;

FIG. 171 is a cross-sectional end view of the retainer of FIG. 168positioned, but not fully inserted, into the staple cartridge channel ofFIG. 170;

FIG. 172 is a plan view of the retainer of FIG. 168 fully inserted inthe staple cartridge channel of FIG. 170;

FIG. 173 is a cross-sectional end view of the retainer of FIG. 168 fullyinserted in the staple cartridge channel of FIG. 170, wherein theretainer is unlocked and is being removed from the staple cartridge;

FIG. 174 is a plan view of an end effector insert in accordance with atleast one embodiment;

FIG. 175 is an elevational view of the end effector insert of FIG. 174;

FIG. 176 is a perspective view of the end effector insert of FIG. 174;

FIG. 177 is a partial perspective view of the end effector insert ofFIG. 174 depicting the end effector insert engaging the anvil of the endeffector of a surgical instrument;

FIG. 178 is a partial perspective view of the end effector insert ofFIG. 174 depicting the end effector insert engaging the staple cartridgeof the end effector of a surgical instrument;

FIG. 179 is an elevational view of the end effector insert of FIG. 174depicting the end effector insert engaging the end effector of asurgical instrument;

FIG. 180 is an elevational view of the end effector insert of FIG. 174positioned in the end effector of a surgical instrument;

FIG. 181 is a partial perspective view of an embodiment of a staplecartridge assembly that includes a staple-cartridge layer and ananvil-attachable layer positioned relative to a staple cartridge;

FIG. 182 is a partial perspective view of the staple cartridge assemblyof FIG. 181, wherein the anvil-attachable layer is fastened to thestaple cartridge;

FIG. 183 is a partial perspective view of an embodiment of a staplecartridge assembly that includes a staple-cartridge layer and ananvil-attachable layer positioned relative to a staple cartridge,wherein a proximal end portion of the anvil-attachable layer is attachedto attachment features of the staple cartridge by an adhesive or by aweld, and wherein a portion of the anvil-attachable layer is shown asbeing transparent for purposes of illustration;

FIG. 184 is a partial perspective view of the staple cartridge assemblyof FIG. 183, wherein a corner of the proximal end portion of theanvil-attachable layer is shown detached and lifted away from the staplecartridge;

FIG. 185 is a partial perspective view of an embodiment of a staplecartridge assembly, that includes a staple cartridge layer and ananvil-attachable layer positioned relative to a staple cartridge,wherein the anvil-attachable layer is attached to the staple cartridgelayer;

FIG. 186 is a detail view of the staple cartridge layer of FIG. 185 andthe anvil-attachable layer attached thereto;

FIG. 187 is a partial plan view of an embodiment of an anvil-attachablelayer;

FIG. 188 is a partial plan view of the anvil-attachable layer of FIG.187 being cut by a cutting blade;

FIG. 189 is a plan view of a tissue compensator of a sleeve inaccordance with at least one embodiment;

FIG. 190 is a perspective view of the tissue compensator of FIG. 189;

FIG. 191 is an elevational view of the tissue compensator of FIG. 189;

FIG. 192 is a perspective view of a tissue thickness compensator;

FIG. 193 is a perspective view of the tissue thickness compensator ofFIG. 192 attached to a staple cartridge;

FIG. 194 is a detail view of one tissue thickness compensator of FIG.192 at least partially overlapped with another tissue thicknesscompensator of FIG. 192;

FIG. 195 is a perspective view of a staple cartridge including a tissuethickness compensator attached thereto;

FIG. 196 is a detail view of one tissue thickness compensator of FIG.195 at least partially overlapped with another tissue thicknesscompensator of FIG. 195;

FIG. 197 is an exploded view of a staple cartridge including a tissuethickness compensator including a plurality of layers;

FIG. 198 is a cross-sectional diagram illustrating a tissue thicknesscompensator of FIG. 197 implanted on one side of patient tissue andanother tissue thickness compensator of FIG. 197 implanted on the otherside of the tissue;

FIG. 199 is an exploded perspective view of an end effector of astapling instrument comprising a staple cartridge and a tissue thicknesscompensator according to various embodiments;

FIG. 200 is a cross sectional view of the tissue thickness compensatorin FIG. 199 according to various embodiments;

FIG. 201 is a top view of a tissue thickness compensator including aplurality of circular pieces according to various embodiments;

FIG. 202 is a top view of a tissue thickness compensator including aplurality of circular pieces according to various embodiments;

FIG. 202A is a cross sectional view of a tissue thickness compensatoraccording to various embodiments;

FIG. 203 is a top view of a tissue thickness compensator according tovarious embodiments;

FIG. 204 is a top view of a tissue thickness compensator including aplurality of hexagonal pieces according to various embodiments;

FIG. 205 is a top view of a fastened tissue thickness compensatorincluding a plurality of pieces according to various embodiments;

FIG. 206 is a top view of a tissue thickness compensator including aplurality of slits according to various embodiments;

FIG. 207A is an exploded view of a staple cartridge and a layer inaccordance with at least one embodiment;

FIG. 207B is a cross-sectional view of a layer and tissue T capturedbetween a staple cartridge and an anvil in accordance with at least oneembodiment;

FIG. 207C is a perspective view of a layer comprising pillar-shapedcleats in accordance with at least one embodiment;

FIG. 208 is a cross-sectional view of the layer in FIG. 207C;

FIG. 209 is a perspective view of a layer comprising linear protrusionsin accordance with at least one embodiment;

FIG. 210 is a cross-sectional view of the layer in FIG. 209;

FIG. 211 is a perspective view of a layer comprising dome-shapedprotrusions in accordance with at least one embodiment;

FIG. 212 is a cross-sectional view of the layer in FIG. 211;

FIG. 213 is a perspective view of a layer comprising linear depressionsin accordance with at least one embodiment;

FIG. 214 is a cross-sectional view of the layer in FIG. 213;

FIG. 215 is a perspective view of a layer comprising linear protrusionsin accordance with at least one embodiment;

FIG. 216 is a cross-sectional view of the layer in FIG. 215;

FIG. 217 is a perspective view of a layer comprising linear protrusionsin accordance with at least one embodiment;

FIG. 218 is a perspective view of a layer comprising cone-shapedprotrusions in accordance with at least one embodiment;

FIG. 219 is a perspective view of a layer comprising pyramid-shapedprotrusions in accordance with at least one embodiment;

FIG. 220 is a cross-sectional view of the layer in FIG. 219 inaccordance with at least one embodiment;

FIG. 221 is a perspective view of a layer in accordance with at leastone embodiment;

FIG. 222 is a cross-sectional view of the layer in FIG. 221;

FIG. 223 is a perspective view of a layer comprising depressions inaccordance with at least one embodiment;

FIG. 224 is a cross-sectional view of the layer in FIG. 223;

FIG. 224A is a cross-sectional view of a layer comprising portions withreduced thickness and tissue T captured between an anvil comprising aplurality of staple forming pockets and a staple cartridge in accordancewith at least one embodiment;

FIG. 224B is a cross-sectional view of a layer comprising a plurality ofprotrusions and tissue T captured between an anvil comprising aplurality of staple forming pockets and a staple cartridge in accordancewith at least one embodiment;

FIG. 225 is a perspective cross-sectional view of a layer, such as atissue thickness compensator, secured to an anvil of an end effector ofa surgical instrument in accordance with at least one embodiment;

FIG. 226 is a cross-sectional view of the layer of FIG. 225 secured tothe anvil;

FIG. 227 is a cross-sectional view of the layer of FIG. 225;

FIG. 228 is a perspective view of an embodiment of a retainer for usewith a staple cartridge;

FIG. 229 is a perspective view of a staple cartridge assembly thatincludes the retainer of FIG. 228 engaged with a staple cartridge and ananvil-attachable layer;

FIG. 230 is a plan view of the staple cartridge assembly of FIG. 229;

FIG. 231 is a cross-sectional end view of the staple cartridge assemblyof FIG. 229, wherein the staple cartridge assembly is inserted into astaple cartridge channel of an end effector and an anvil of the endeffector is positioned relative thereto;

FIG. 232 is a cross-sectional end view of the staple cartridge assemblyand end effector shown in FIG. 231, wherein the anvil is pressed againstthe anvil-attachable layer and the retainer;

FIG. 233 is a cross-sectional plan view of the staple cartridge assemblyand end effector shown in FIG. 231, wherein the anvil has been liftedfrom the retainer, removing the attached anvil-attachable layer from theretainer;

FIG. 234 is a cross-sectional plan view of the end effector shown inFIG. 231, wherein the anvil-attachable layer is attached to the anviland the retainer has been removed;

FIG. 235 is a perspective view of an embodiment of an anvil-attachablelayer in accordance with at least one embodiment;

FIG. 236 is a perspective view of an embodiment of an anvil-attachablelayer in accordance with at least one embodiment;

FIG. 237 is a perspective view of an embodiment of an anvil-attachablelayer in accordance with at least one embodiment;

FIG. 238 is a perspective view of an embodiment of an anvil-attachablelayer with deployable attachment features, wherein the deployableattachment features are in an undeployed configuration;

FIG. 239 is a perspective view of the anvil-attachable layer of FIG.238, wherein the deployable attachment features are shown in a deployedconfiguration;

FIG. 240 is a cross-sectional plan view of the anvil-attachable layer ofFIG. 238 positioned relative to an anvil of an end effector, wherein thedeployable attachment features are deployed in a slot of the anvil;

FIG. 241 is a perspective view of an embodiment of an anvil-attachablelayer with deployable attachment features, wherein the deployableattachment features are in an undeployed configuration;

FIG. 242 is a perspective view of the anvil-attachable layer of FIG.241, wherein the deployable attachment features are shown in a deployedconfiguration;

FIG. 243 is a cross-sectional plan view of the anvil-attachable layer ofFIG. 241 positioned relative to an anvil of an end effector, wherein thedeployable attachment features are deployed in a slot of the anvil;

FIG. 244 is an exploded perspective view of an anvil and a tissuethickness compensator in accordance with at least one embodiment;

FIG. 245 is a cross-sectional plan view of an anvil comprising aplurality of staple forming pockets and an anvil-attachable layer, suchas a tissue thickness compensator, comprising a plurality of capsulesaligned with the forming pockets in accordance with at least oneembodiment;

FIG. 246 is a detail view of the capsules of the anvil-attachable layerof FIG. 245;

FIG. 247 is a diagram illustrating the anvil and the anvil-attachablelayer of FIG. 245 positioned relative to tissue which is to be stapledby staples from a staple cartridge positioned on the opposite side ofthe tissue;

FIG. 248 is a diagram illustrating the anvil of FIG. 245 moved towardthe staple cartridge of FIG. 247 and staples partially fired from thestaple cartridge;

FIG. 249 is a cross-sectional view of an embodiment of ananvil-attachable layer arranged relative to an anvil and patient tissue,wherein staples of a staple cartridge are fired through the layer andthe patient tissue;

FIG. 250 is a cross-sectional view of an embodiment of ananvil-attachable layer positioned relative to an anvil and patienttissue, wherein staples of a staple cartridge are fired through thelayer and the patient tissue;

FIG. 251 illustrates a retainer assembly being inserted into a surgicalinstrument, wherein the surgical instrument comprises an anvil and astaple cartridge channel, and wherein a portion of the insertion tool isremoved for the purposes of illustration;

FIG. 252 illustrates the retainer assembly of FIG. 251 being insertedinto the surgical instrument, wherein a portion of the insertion tool isremoved for the purposes of illustration;

FIG. 253 illustrates the insertion tool of FIG. 251 being moved relativeto the retainer to engage the staple cartridge in the staple cartridgechannel and to engage an anvil-attachable layer, such as a tissuethickness compensator, with the anvil, wherein a portion of theinsertion tool is removed for the purposes of illustration;

FIG. 254 illustrates the insertion tool of FIG. 251 being moved relativeto the retainer to disengage the retainer from the anvil-attachablelayer and from the staple cartridge, wherein a portion of the insertiontool is removed for the purposes of illustration;

FIG. 255 is a perspective view of an embodiment of a retainer engagedwith a staple cartridge, wherein an anvil-attachable layer havingdeployable attachment features engaged with the retainer, and whereinthe retainer is positioned for insertion into an end effector;

FIG. 256 is a perspective view of the retainer of FIG. 255;

FIG. 257 is an elevational view of the retainer of FIG. 255;

FIG. 258 is an elevational view of the retainer, staple cartridge andanvil-attachable layer of FIG. 255 inserted into an end effector,wherein the deployable attachment features of the anvil-attachable layerare deployed, and wherein portions of the anvil and the anvil-attachablelayer are removed for purposes of illustration;

FIG. 259 is an elevational view of an embodiment of a retainer insertedin an end effector, wherein an anvil-attachable layer with deployableattachment features is arranged on the retainer, and wherein portions ofthe retainer, the anvil-attachable layer, and the anvil are removed forpurposes of illustration;

FIG. 260 is an elevational view of the retainer of FIG. 259, wherein theretainer has deployed the deployable attachment features of theanvil-attachable layer, and wherein portions of the retainer, theanvil-attachable layer, and the anvil are removed for purposes ofillustration;

FIG. 261 is a detail elevational view of the retainer, anvil-attachablelayer, and anvil of FIG. 259, wherein the deployable attachment featuresare not deployed, and wherein portions of the retainer, anvil-attachablelayer, and anvil are removed for purposes of illustration;

FIG. 262 is a detail elevational view of the retainer, anvil-attachablelayer, and anvil of FIG. 259, wherein the deployable attachment featuresare deployed into a slot in the anvil, and wherein portions of theretainer, anvil-attachable layer, and anvil are removed for purposes ofillustration;

FIG. 263 illustrates a tissue thickness compensator comprising aflowable attachment portion according to certain non-limitingembodiments;

FIG. 264 illustrates a pressure sensitive adhesive laminate in anunstressed position aligned with a slot in the staple cartridgeaccording to certain non-limiting embodiments;

FIG. 265 illustrates the pressure sensitive adhesive laminate in FIG.264 releasably attached to a staple cartridge according to certainnon-limiting embodiments;

FIG. 266 illustrates a tissue thickness compensator comprising aflowable attachment portion according to certain non-limitingembodiments;

FIG. 267 illustrates a pressure sensitive adhesive laminate in anunstressed position aligned with staple cavities in the staple cartridgeaccording to certain non-limiting embodiments;

FIG. 268 illustrates the pressure sensitive adhesive laminate in FIG.267 releasably attached to a staple cartridge according to certainnon-limiting embodiments;

FIGS. 269-273 illustrate a pressure sensitive adhesive laminatecomprising an adhesive tab according to certain non-limitingembodiments;

FIGS. 274-279 illustrate a pressure sensitive adhesive laminatecomprising an adhesive tab according to certain non-limitingembodiments;

FIGS. 280-283 illustrate a pressure sensitive adhesive laminatecomprising tabs to releasably attach to an anvil according to certainnon-limiting embodiments;

FIGS. 284-288 illustrate a pressure sensitive adhesive laminatereleasably attached to an anvil using an applicator according to certainnon-limiting embodiments;

FIGS. 289-292 illustrate a pressure sensitive adhesive laminatereleasably attached to an anvil according to certain non-limitingembodiments;

FIG. 293 is a perspective view of an end effector of a surgical staplinginstrument including an implantable transition portion extending fromthe anvil and an implantable transition portion extending from thestaple cartridge; and

FIG. 294 is a diagram depicting tissue positioned between the anvil andthe staple cartridge of the surgical stapling instrument of FIG. 293.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate certain embodiments of the invention, in one form, and suchexemplifications are not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

The Applicant of the present application also owns the U.S. patentapplications identified below which are each herein incorporated byreference in their respective entirety:

U.S. patent application Ser. No. 12/894,311, entitled SURGICALINSTRUMENTS WITH RECONFIGURABLE SHAFT SEGMENTS, now U.S. PatentPublication No. 2012/0080496;

U.S. patent application Ser. No. 12/894,340, entitled SURGICAL STAPLECARTRIDGES SUPPORTING NON-LINEARLY ARRANGED STAPLES AND SURGICALSTAPLING INSTRUMENTS WITH COMMON STAPLE-FORMING POCKETS, now U.S. PatentPublication No. 2012/0080482;

U.S. patent application Ser. No. 12/894,327, entitled JAW CLOSUREARRANGEMENTS FOR SURGICAL INSTRUMENTS, now U.S. Patent Publication No.2012/0080499;

U.S. patent application Ser. No. 12/894,351, entitled SURGICAL CUTTINGAND FASTENING INSTRUMENTS WITH SEPARATE AND DISTINCT FASTENER DEPLOYMENTAND TISSUE CUTTING SYSTEMS, now U.S. Patent Publication No.2012/0080502;

U.S. patent application Ser. No. 12/894,338, entitled IMPLANTABLEFASTENER CARTRIDGE HAVING A NON-UNIFORM ARRANGEMENT, now U.S. PatentPublication No. 2012/0080481;

U.S. patent application Ser. No. 12/894,369, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING A SUPPORT RETAINER, now U.S. PatentPublication No. 2012/0080344;

U.S. patent application Ser. No. 12/894,312, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING MULTIPLE LAYERS, now U.S. PatentPublication No. 2012/0080479;

U.S. patent application Ser. No. 12/894,377, entitled SELECTIVELYORIENTABLE IMPLANTABLE FASTENER CARTRIDGE, now U.S. Patent PublicationNo. 2012/0080334;

U.S. patent application Ser. No. 12/894,339, entitled SURGICAL STAPLINGINSTRUMENT WITH COMPACT ARTICULATION CONTROL ARRANGEMENT, now U.S.Patent Publication No. 2012/0080500;

U.S. patent application Ser. No. 12/894,360, entitled SURGICAL STAPLINGINSTRUMENT WITH A VARIABLE STAPLE FORMING SYSTEM, now U.S. PatentPublication No. 2012/0080484;

U.S. patent application Ser. No. 12/894,322, entitled SURGICAL STAPLINGINSTRUMENT WITH INTERCHANGEABLE STAPLE CARTRIDGE ARRANGEMENTS, now U.S.Patent Publication No. 2012/0080501;

U.S. patent application Ser. No. 12/894,350, entitled SURGICAL STAPLECARTRIDGES WITH DETACHABLE SUPPORT STRUCTURES AND SURGICAL STAPLINGINSTRUMENTS WITH SYSTEMS FOR PREVENTING ACTUATION MOTIONS WHEN ACARTRIDGE IS NOT PRESENT, now U.S. Patent Publication No. 2012/0080478;

U.S. patent application Ser. No. 12/894,383, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING BIOABSORBABLE LAYERS, now U.S. PatentPublication No. 2012/0080345;

U.S. patent application Ser. No. 12/894,389, entitled COMPRESSIBLEFASTENER CARTRIDGE, now U.S. Patent Publication No. 2012/0080335;

U.S. patent application Ser. No. 12/894,345, entitled FASTENERSSUPPORTED BY A FASTENER CARTRIDGE SUPPORT, now U.S. Patent PublicationNo. 2012/0080483;

U.S. patent application Ser. No. 12/894,306, entitled COLLAPSIBLEFASTENER CARTRIDGE, now U.S. Patent Publication No. 2012/0080332;

U.S. patent application Ser. No. 12/894,318, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF CONNECTED RETENTION MATRIX ELEMENTS, now U.S.Patent Publication No. 2012/0080480;

U.S. patent application Ser. No. 12/894,330, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND AN ALIGNMENT MATRIX, now U.S. PatentPublication No. 2012/0080503;

U.S. patent application Ser. No. 12/894,361, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX, now U.S. Patent Publication No.2012/0080333;

U.S. patent application Ser. No. 12/894,367, entitled FASTENINGINSTRUMENT FOR DEPLOYING A FASTENER SYSTEM COMPRISING A RETENTIONMATRIX, now U.S. Patent Publication No. 2012/0080485;

U.S. patent application Ser. No. 12/894,388, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND A COVER, now U.S. Patent PublicationNo. 2012/0080487;

U.S. patent application Ser. No. 12/894,376, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF FASTENER CARTRIDGES, now U.S. PatentPublication No. 2012/0080486;

U.S. patent application Ser. No. 13/097,865, entitled SURGICAL STAPLERANVIL COMPRISING A PLURALITY OF FORMING POCKETS, now U.S. PatentPublication No. 2012/0080488;

U.S. patent application Ser. No. 13/097,936, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER, now U.S. Patent Publication No.2012/0080339;

U.S. patent application Ser. No. 13/097,954, entitled STAPLE CARTRIDGECOMPRISING A VARIABLE THICKNESS COMPRESSIBLE PORTION, now U.S. PatentPublication No. 2012/0080340;

U.S. patent application Ser. No. 13/097,856, entitled STAPLE CARTRIDGECOMPRISING STAPLES POSITIONED WITHIN A COMPRESSIBLE PORTION THEREOF, nowU.S. Patent Publication No. 2012/0080336;

U.S. patent application Ser. No. 13/097,928, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING DETACHABLE PORTIONS, now U.S. Patent PublicationNo. 2012/0080490;

U.S. patent application Ser. No. 13/097,891, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER COMPRISING AN ADJUSTABLE ANVIL, nowU.S. Patent Publication No. 2012/0080489;

U.S. patent application Ser. No. 13/097,948, entitled STAPLE CARTRIDGECOMPRISING AN ADJUSTABLE DISTAL PORTION, now U.S. Patent Publication No.2012/0083836;

U.S. patent application Ser. No. 13/097,907, entitled COMPRESSIBLESTAPLE CARTRIDGE ASSEMBLY, now U.S. Patent Publication No. 2012/0080338;

U.S. patent application Ser. No. 13/097,861, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING PORTIONS HAVING DIFFERENT PROPERTIES, now U.S.Patent Publication No. 2012/0080337;

U.S. patent application Ser. No. 13/097,869, entitled STAPLE CARTRIDGELOADING ASSEMBLY, now U.S. Patent Publication No. 2012/0160721;

U.S. patent application Ser. No. 13/097,917, entitled COMPRESSIBLESTAPLE CARTRIDGE COMPRISING ALIGNMENT MEMBERS, now U.S. PatentPublication No. 2012/0083834;

U.S. patent application Ser. No. 13/097,873, entitled STAPLE CARTRIDGECOMPRISING A RELEASABLE PORTION, now U.S. Patent Publication No.2012/0083833;

U.S. patent application Ser. No. 13/097,938, entitled STAPLE CARTRIDGECOMPRISING COMPRESSIBLE DISTORTION RESISTANT COMPONENTS, now U.S. PatentPublication No. 2012/0080491;

U.S. patent application Ser. No. 13/097,924, entitled STAPLE CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR, now U.S. Patent PublicationNo. 2012/0083835;

U.S. patent application Ser. No. 13/242,029, entitled SURGICAL STAPLERWITH FLOATING ANVIL, now U.S. Patent Publication No. 2012/0080493;

U.S. patent application Ser. No. 13/242,066, entitled CURVED ENDEFFECTOR FOR A STAPLING INSTRUMENT, now U.S. Patent Publication No.2012/0080498;

U.S. patent application Ser. No. 13/242,086, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK;

U.S. patent application Ser. No. 13/241,912, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK ARRANGEMENT;

U.S. patent application Ser. No. 13/241,922, entitled SURGICAL STAPLERWITH STATIONARY STAPLE DRIVERS;

U.S. patent application Ser. No. 13/241,637, entitled SURGICALINSTRUMENT WITH TRIGGER ASSEMBLY FOR GENERATING MULTIPLE ACTUATIONMOTIONS, now U.S. Patent Publication No. 2012/0074201;

U.S. patent application Ser. No. 13/241,629, entitled SURGICALINSTRUMENT WITH SELECTIVELY ARTICULATABLE END EFFECTOR, now U.S. PatentPublication No. 2012/0074200;

U.S. application Ser. No. 13/433,096, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF CAPSULES, now U.S. PatentPublication No. 2012/0241496;

U.S. application Ser. No. 13/433,103, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF LAYERS, now U.S. PatentPublication No. 2012/0241498;

U.S. application Ser. No. 13/433,098, entitled EXPANDABLE TISSUETHICKNESS COMPENSATOR, now U.S. Patent Publication No. 2012/0241491;

U.S. application Ser. No. 13/433,102, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A RESERVOIR, now U.S. Patent Publication No.2012/0241497;

U.S. application Ser. No. 13/433,114, entitled RETAINER ASSEMBLYINCLUDING A TISSUE THICKNESS COMPENSATOR, now U.S. Patent PublicationNo. 2012/0241499;

U.S. application Ser. No. 12/433,136, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING AT LEAST ONE MEDICAMENT, now U.S. PatentPublication No. 2012/0241492;

U.S. application Ser. No. 13/433,141, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CONTROLLED RELEASE AND EXPANSION, now U.S. PatentPublication No. 2012/0241493;

U.S. application Ser. No. 13/433,144, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING FIBERS TO PRODUCE A RESILIENT LOAD, now U.S.Patent Publication No. 2012/0241500;

U.S. application Ser. No. 13/433,148, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING STRUCTURE TO PRODUCE A RESILIENT LOAD, now U.S.Patent Publication No. 2012/0241501;

U.S. application Ser. No. 13/433,155, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING RESILIENT MEMBERS, now U.S. Patent PublicationNo. 2012/0241502;

U.S. application Ser. No. 13/433,163, entitled METHODS FOR FORMINGTISSUE THICKNESS COMPENSATOR ARRANGEMENTS FOR SURGICAL STAPLERS, nowU.S. Patent Publication No. 2012/0248169;

U.S. application Ser. No. 13/433,167, entitled TISSUE THICKNESSCOMPENSATORS, now U.S. Patent Publication No. 2012/0241503;

U.S. application Ser. No. 13/433,175, entitled LAYERED TISSUE THICKNESSCOMPENSATOR, now U.S. Patent Publication No. 2012/0253298;

U.S. application Ser. No. 13/433,179, entitled TISSUE THICKNESSCOMPENSATORS FOR CIRCULAR SURGICAL STAPLERS, now U.S. Patent PublicationNo. 2012/0241505;

U.S. application Ser. No. 13/433,115, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CAPSULES DEFINING A LOW PRESSURE ENVIRONMENT;

U.S. application Ser. No. 13/433,118, entitled TISSUE THICKNESSCOMPENSATOR COMPRISED OF A PLURALITY OF MATERIALS;

U.S. application Ser. No. 13/433,135, entitled MOVABLE MEMBER FOR USEWITH A TISSUE THICKNESS COMPENSATOR;

U.S. application Ser. No. 13/433,140, entitled TISSUE THICKNESSCOMPENSATOR AND METHOD FOR MAKING THE SAME;

U.S. application Ser. No. 13/433,147, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CHANNELS;

U.S. application Ser. No. 13/433,126, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING TISSUE INGROWTH FEATURES;

U.S. application Ser. No. 13/433,132, entitled DEVICES AND METHODS FORATTACHING TISSUE THICKNESS COMPENSATING MATERIALS TO SURGICAL STAPLINGINSTRUMENTS; and

U.S. application Ser. No. 13/433,129, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF MEDICAMENTS.

The Applicant of the present application also owns the U.S. patentapplications identified below which are each herein incorporated byreference in their respective entirety:

U.S. application Ser. No. 11/216,562, entitled STAPLE CARTRIDGES FORFORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. Pat.No. 7,669,746;

U.S. application Ser. No. 11/714,049, entitled SURGICAL STAPLING DEVICEWITH ANVIL HAVING STAPLE FORMING POCKETS OF VARYING DEPTHS, now U.S.Patent Publication No. 2007/0194082;

U.S. application Ser. No. 11/711,979, entitled SURGICAL STAPLING DEVICESTHAT PRODUCE FORMED STAPLES HAVING DIFFERENT LENGTHS, now U.S. Pat. No.8,317,070;

U.S. application Ser. No. 11/711,975, entitled SURGICAL STAPLING DEVICEWITH STAPLE DRIVERS OF DIFFERENT HEIGHT, now U.S. Patent Publication No.2007/0194079;

U.S. application Ser. No. 11/711,977, entitled SURGICAL STAPLING DEVICEWITH STAPLE DRIVER THAT SUPPORTS MULTIPLE WIRE DIAMETER STAPLES, nowU.S. Pat. No. 7,673,781;

U.S. application Ser. No. 11/712,315, entitled SURGICAL STAPLING DEVICEWITH MULTIPLE STACKED ACTUATOR WEDGE CAMS FOR DRIVING STAPLE DRIVERS,now U.S. Pat. No. 7,500,979;

U.S. application Ser. No. 12/038,939, entitled STAPLE CARTRIDGES FORFORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. Pat.No. 7,934,630;

U.S. application Ser. No. 13/020,263, entitled SURGICAL STAPLING SYSTEMSTHAT PRODUCE FORMED STAPLES HAVING DIFFERENT LENGTHS, now U.S. PatentPublication No. 2011/0147434;

U.S. application Ser. No. 13/118,278, entitled ROBOTICALLY-CONTROLLEDSURGICAL STAPLING DEVICES THAT PRODUCE FORMED STAPLES HAVING DIFFERENTLENGTHS, now U.S. Patent Publication No. 2011/0290851;

U.S. application Ser. No. 13/369,629, entitled ROBOTICALLY-CONTROLLEDCABLE-BASED SURGICAL END EFFECTORS, now U.S. Patent Publication No.2012/0138660;

U.S. application Ser. No. 12/695,359, entitled SURGICAL STAPLING DEVICESFOR FORMING STAPLES WITH DIFFERENT FORMED HEIGHTS, now U.S. PatentPublication No. 2010/0127042; and

U.S. application Ser. No. 13/072,923, entitled STAPLE CARTRIDGES FORFORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. PatentPublication No. 2011/0174863.

The Applicant of the present application also owns the U.S. patentapplications identified below which were filed on even date herewith andwhich are each herein incorporated by reference in their respectiveentirety:

U.S. application Ser. No. ______, entitled SURGICAL STAPLING CARTRIDGEWITH LAYER RETENTION FEATURES, (Attorney Docket No.END7104USCIP1/110606CIP1);

U.S. application Ser. No. ______, entitled ADHESIVE FILM LAMINATE,(Attorney Docket No. END6843USCIP19/100528CP19);

U.S. application Ser. No. ______, entitled ACTUATOR FOR RELEASING ATISSUE THICKNESS COMPENSATOR FROM A FASTENER CARTRIDGE, (Attorney DocketNo. END6848USCIP2/100533CIP2);

U.S. application Ser. No. ______, entitled RELEASABLE TISSUE THICKNESSCOMPENSATOR AND FASTENER CARTRIDGE HAVING THE SAME, (Attorney Docket No.END6848USCIP3/100533CIP3);

U.S. application Ser. No. ______, entitled FASTENER CARTRIDGE COMPRISINGA RELEASABLE TISSUE THICKNESS COMPENSATOR, (Attorney Docket No.END6848USCIP4/100533CIP4);

U.S. application Ser. No. ______, entitled FASTENER CARTRIDGE COMPRISINGA RELEASABLY ATTACHED TISSUE THICKNESS COMPENSATOR, (Attorney Docket No.END6848USCIP6/100533CIP6);

U.S. application Ser. No. ______, entitled STAPLE CARTRIDGE COMPRISING ARELEASABLE COVER, (Attorney Docket No. END7201USNP/120294);

U.S. application Ser. No. ______, entitled ANVIL LAYER ATTACHED TO APROXIMAL END OF AN END EFFECTOR, (Attorney Docket No.END7102USCIP2/110604CIP2);

U.S. application Ser. No. ______, entitled LAYER COMPRISING DEPLOYABLEATTACHMENT MEMBERS, (Attorney Docket No. END7102USCIP3/110604CIP3);

U.S. application Ser. No. ______, entitled END EFFECTOR COMPRISING ADISTAL TISSUE ABUTMENT MEMBER, (Attorney Docket No.END7102USCIP4/110604CIP4);

U.S. application Ser. No. ______, entitled LAYER ARRANGEMENTS FORSURGICAL STAPLE CARTRIDGES, (Attorney Docket No.END6232USCIP1/070348CIP1);

U.S. application Ser. No. ______, entitled IMPLANTABLE ARRANGEMENTS FORSURGICAL STAPLE CARTRIDGES, (Attorney Docket No.END6232USCIP2/070348CIP2);

U.S. application Ser. No. ______, entitled MULTIPLE THICKNESSIMPLANTABLE LAYERS FOR SURGICAL STAPLING DEVICES, (Attorney Docket No.END6840USCIP2/100525CIP2);

U.S. application Ser. No. ______, entitled RELEASABLE LAYER OF MATERIALAND SURGICAL END EFFECTOR HAVING THE SAME, (Attorney Docket No.END6232USCIP3/070348CIP3);

U.S. application Ser. No. ______, entitled ACTUATOR FOR RELEASING ALAYER OF MATERIAL FROM A SURGICAL END EFFECTOR, (Attorney Docket No.END6232USCIP4/070348CIP4); and

U.S. application Ser. No. ______, entitled STAPLE CARTRIDGE COMPRISING ACOMPRESSIBLE PORTION, (Attorney Docket No. END7200USNP/120302).

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those of ordinary skill in the art will understand that thedevices and methods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the various embodiments of the present invention is definedsolely by the claims. The features illustrated or described inconnection with one exemplary embodiment may be combined with thefeatures of other embodiments. Such modifications and variations areintended to be included within the scope of the present invention.

Reference throughout the specification to “various embodiments,” “someembodiments,” “one embodiment,” or “an embodiment”, or the like, meansthat a particular feature, structure, or characteristic described inconnection with the embodiment is included in at least one embodiment.Thus, appearances of the phrases “in various embodiments,” “in someembodiments,” “in one embodiment”, or “in an embodiment”, or the like,in places throughout the specification are not necessarily all referringto the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments. Thus, the particular features, structures, orcharacteristics illustrated or described in connection with oneembodiment may be combined, in whole or in part, with the featuresstructures, or characteristics of one or more other embodiments withoutlimitation. Such modifications and variations are intended to beincluded within the scope of the present invention.

The terms “proximal” and “distal” are used herein with reference to aclinician manipulating the handle portion of the surgical instrument.The term “proximal” referring to the portion closest to the clinicianand the term “distal” referring to the portion located away from theclinician. It will be further appreciated that, for convenience andclarity, spatial terms such as “vertical”, “horizontal”, “up”, and“down” may be used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and/or absolute.

Various exemplary devices and methods are provided for performinglaparoscopic and minimally invasive surgical procedures. However, theperson of ordinary skill in the art will readily appreciate that thevarious methods and devices disclosed herein can be used in numeroussurgical procedures and applications including, for example, inconnection with open surgical procedures. As the present DetailedDescription proceeds, those of ordinary skill in the art will furtherappreciate that the various instruments disclosed herein can be insertedinto a body in any way, such as through a natural orifice, through anincision or puncture hole formed in tissue, etc. The working portions orend effector portions of the instruments can be inserted directly into apatient's body or can be inserted through an access device that has aworking channel through which the end effector and elongated shaft of asurgical instrument can be advanced.

In FIGS. 1 and 2, a surgical stapling and severing instrument 8010 cancomprise an anvil 8014 which may be repeatably opened and closed aboutits pivotal attachment to an elongate staple channel 8016. A stapleapplying assembly 8012 can comprise the anvil 8014 and the channel 8016,wherein the assembly 8012 can be proximally attached to the elongateshaft 8018 forming an implement portion 8022. When the staple applyingassembly 8012 is closed, or at least substantially closed, the implementportion 8022 can present a sufficiently small cross-section suitable forinserting the staple applying assembly 8012 through a trocar. In variousembodiments, the assembly 8012 can be manipulated by a handle 8020connected to the shaft 8018. The handle 8020 can comprise user controlssuch as a rotation knob 8030 that rotates the elongate shaft 8018 andstaple applying assembly 8012 about a longitudinal axis of the shaft8018. A closure trigger 8026, which can pivot in front of a pistol grip8036 about a closure trigger pin 8152 (FIG. 3) engaged laterally acrossthe handle housing 8154, can be depressed to close the staple applyingassembly 8012. In various embodiments, a closure release button 8038 canbe outwardly presented on the handle 8020 when the closure trigger 8026is clamped such that the release button 8038 can be depressed to unclampthe closure trigger 8026 and open the staple applying assembly 8012, asdescribed in greater detail below. A firing trigger 8034, which canpivot in front of the closure trigger 8026, can cause the stapleapplying assembly 8012 to simultaneously sever and staple tissue clampedtherein. In various circumstances, as described in greater detail below,multiple firing strokes can be employed using the firing trigger 8034 toreduce the amount of force required to be applied by the surgeon's handper stroke. In certain embodiments, the handle 8020 can compriserotatable right and/or left indicator wheels 8040, 8041 (FIG. 3) whichcan indicate the firing progress. For instance, full firing travel mayrequire three full firing strokes of firing trigger 8034 and thus theindicator wheels 8040, 8041 can rotate up to one-third of a revolutioneach per stroke of firing trigger 8034. As described in greater detailbelow, a manual firing release lever 8042 can allow the firing system tobe retracted before full firing travel has been completed, if desired,and, in addition, the firing release lever 8042 can allow a surgeon, orother clinician, to retract the firing system in the event that thefiring system binds and/or fails.

With reference to FIGS. 1 and 3, the elongate shaft 8018 can comprise anouter structure including a longitudinally reciprocating closure tube8024 that pivots the anvil 8014 toward its close position in response tothe proximal depression of the closure trigger 8026 of handle 8020. Theelongate channel 8018 can be connected to the handle 8020 by a frame8028 (FIG. 3) that is internal to the closure tube 8024. The frame 8028can be rotatably engaged to the handle 8020 so that the rotation of therotation knob 8030 (FIG. 1) can rotate the implement portion 8022. Withparticular reference to FIG. 3, the rotation knob 8030 can be comprisedof two half-shells which can include one or more inward projections 8031that can extend through one or more elongate side openings 8070 in theclosure tube 8024 and engage the frame 8028. As a result of the above,the rotation knob 8030 and the frame 8028 can be rotated together, orsynchronously, such that the rotated position of knob 8030 determinesthe rotated position of the implement portion 8022. In variousembodiments, the longitudinal length of the longer opening 8070 issufficiently long to allow the longitudinal closure motion, and openingmotion, of the closure tube 8024. With regard to generating the closuremotion of closure tube 8024, referring primarily to FIGS. 3 and 5, anupper portion 8160 of the closure trigger 8026 can push forward aclosure yoke 8162 (FIG. 4) via a closure link 8164. The closure link8164 is pivotally attached at its distal end by a closure yoke pin 8166to the closure yoke 8162 and is pivotally attached at its proximal endby a closure link pin 8168. In various embodiments, the closure trigger8026 can be urged to an open position by a closure trigger tensionspring 8246 that is connected proximally to the upper portion 8160 ofthe closure trigger 8026 and a handle housing 8154 formed by right andleft half shells 8156, 8158. The tension force applied by the tensionspring 8246 can be overcome by a closing force applied to the closuretrigger 8026 in order to advance the yoke 8162, closure link 8164, andthe closure tube 8024 distally.

As the closure trigger 8026 is actuated, or depressed, as describedabove, the closure release button 8038 can be positioned such that thesurgeon, or other clinician, can push the closure release button 8038,if desired, and allow the closure trigger 8026, and the rest of thesurgical instrument, to return to an unactuated state. In variousembodiments, the closure release button 8038 can be connected to apivoting locking arm 8172 by a central lateral pivot 8173 such thatmotion can be transferred between the release button 8038 and thelocking arm 8172. Referring again to FIG. 3, a compression spring 8174can bias the closure release button 8038 proximally, i.e., clockwiseabout the central lateral pivot 8173 as viewed from the right and theupper portion 8160 of the closure trigger 8026 can include a proximalcrest 8170 with an aft notch 8171. As the closure trigger 8026 isdepressed, the pivoting locking arm 8172 can ride upon the proximalcrest 8170 and when the closure trigger 8026 reaches its fully depressedposition, it should be appreciated that the aft notch 8171 is presentedbelow the pivoting locking arm 8172 which drops into and locks againstthe aft notch 8171 under the urging of the compression spring 8174. Atsuch point, manual depression of the closure release button 8038 rotatesthe pivoting locking arm 8172 upward and out of aft notch 8171 therebyunlocking the closure trigger 8026 and allowing the closure trigger 8026to be returned to its unclamped position.

Once the closure trigger 8026 is proximally clamped, as discussed above,the firing trigger 8034 can be drawn toward the pistol grip 8036 inorder to advance a firing rod 8032 distally from the handle 8020. Invarious embodiments, the firing trigger 8034 can pivot about a firingtrigger pin 8202 that laterally traverses and is engaged with the rightand left half shells 8156, 8158 of the handle 8020. The firing trigger8034, when actuated, can advance a linked transmission firing mechanism8150. The linked transmission firing mechanism 8150 can be urged into aretracted, unfired, position by a spring 8184 that is, one, attached tothe pistol grip 8036 of the handle 8020 and, two, attached to one of thelinks, for example, of the linked transmission firing mechanism 8150 asdescribed in greater detail below. The spring 8184 can comprise anonmoving end 8186 connected to the housing 8154 and a moving end 8188connected to a proximal end 8190 of a steel band 8192. Adistally-disposed end 8194 of the steel band 8192 can be attached to anattachment feature 8195 on a front link 8196 a of a plurality of links8196 a-8196 d that form a linked rack 8200. Linked rack 8200 can beflexible such that it can readily retract into the pistol grip 8036 andminimize the length of the handle 8020 and yet form a straight rigidrack assembly that may transfer a significant firing force to and/orthrough the firing rod 8032. As described in greater detail below, thefiring trigger 8034 can be engaged with a first link 8196 a during afirst actuation of the firing trigger 8034, engaged with a second link8196 b during a second actuation of the firing trigger 8034, engagedwith a third link 8196 c during a third actuation of the firing trigger8034, and engaged with a fourth link 8196 d during a fourth actuation ofthe firing trigger 8034, wherein each actuation of the firing trigger8034 can advance the linked rack 8200 distally an incremental amount. Invarious embodiments, further to the above, the multiple strokes offiring trigger 8034 can rotate the right and left indicator gauge wheels8040, 8041 to indicate the distance in which the linked rack 8200 hasbeen advanced.

Referring now to FIGS. 3 and 5, an anti-backup mechanism 8250 canprevent the combination tension/compression spring 8184 from retractingthe linked rack 8200 between firing strokes. In various embodiments, acoupling slide tube 8131 abuts the first link 8196 a and connects to thefiring rod 8032 to communicate the firing motion. The firing rod 8032extends proximally out of a proximal end of the frame 8028 and through athrough hole 8408 of an anti-backup plate 8266. The through hole 8408 issized to slidingly receive the firing rod 8032 when perpendicularlyaligned but to bind when tipped. A lower tab attachment 8271 extendsproximally from a lower lip of the proximal end of the frame 8028,extending through an aperture 8269 on a lower edge of the anti-backupplate 8266. This lower tab attachment 8271 draws the lower portion ofthe anti-backup plate 8266 proximate to the frame 8028 so that theanti-backup plate 8266 is perpendicular when the firing rod 8032 isdistally advanced and allowed to tip top aft into a binding state whenthe firing rod 8032 attempts to retract. An anti-backup compressionspring 8264 is distally constrained by the proximal end of the frame8028 and proximally abuts a top portion of the anti-backup plate 8266,biasing the anti-backup plate 8266 to a locking state. Opposing thespring bias, an anti-backup cam tube 8268 slidingly encompasses thecoupling slide tube 8131 and abuts the anti-backup plate 8266. Aproximally projecting anti-backup yoke 8256 attached to the anti-backupcam tube 8268 extends overtop of the closure yoke 8162.

Referring to FIG. 3, a link triggered automatic retraction mechanism8289 is incorporated into the surgical stapling and severing instrument8010 to cause knife retraction at the end of full firing travel. To thatend, the distal link 8196 d includes a tang 8290 that projects upwardlywhen the distal link 8196 d is advanced into rack channel 8291 (FIG. 3)formed in the closure yoke 8162. This tang 8290 is aligned to activate abottom proximal cam 8292 on an anti-backup release lever 8248 (FIG. 6).With particular reference to FIG. 6, structures formed in the right andleft half shells 8156, 8158 constrain movement of the anti-backuprelease lever 8248. A pin receptacle 8296 and circular pin 8293 formedrespectively between right and left half shells 8156, 8158 is receivedthrough a longitudinally elongate aperture 8294 formed in theanti-backup release lever 8248 distal to the bottom proximal cam 8292,thus allowing longitudinal translation as well as rotation about thecircular pin 8293. In the right half shell 8156, a proximally openchannel includes a proximal horizontal portion that communicates with anupwardly and distally angled portion that receives a rightward aft pin8297 near the proximal end of the anti-backup release lever 8248, thusimparting an upward rotation as the anti-backup release lever 8248reaches the distal most portion of its translation. A blocking structureformed in the right half shell 8156 proximal to the anti-backup releaselever 8248 prevents proximal movement thereof once assembled to maintainrightward aft pin 8297 in the proximally open channel, discussed above.

Further to the above, referencing now FIGS. 3 and 7, a distal end 8254of the anti-backup release lever 8248 thus is urged distally anddownwardly, causing a rightward front pin 8298 to drop into distallyopen step structure 8299 formed in the right half shell 8156, which isurged into this engagement by a compression spring 8300 (FIG. 3) hookedto a leftward hook 8301 on the anti-backup release lever 8248 betweenthe rightward front pin 8298 and the longitudinally elongate aperture8294. The other end of the compression spring 8300 is attached to a hook8302 (FIG. 6) formed in the right half shell 8156 in a more proximal andlower position just above the closure yoke 8266. The compression spring8300 thus pulls the distal end 8254 of the anti-backup release lever8248 down and aft, which results in the rightward front pin 8298 lockinginto the distally open step structure 8299 when distally advanced. Thus,once tripped, referring to FIG. 7, the anti-backup release lever 8248remains forward holding the anti-backup plate 8266 perpendicularly andthus allowing the linked rack 8200 to be retracted. When the closureyoke 8266 is subsequently retracted when unclamping the end effector8012, an upwardly projecting reset tang 8303 on the closure yoke 8266contacts a bottom distal cam 8305 of the anti-backup release lever 8248,lifting the rightward front pin 8298 out of the distally open stepstructure 8299 so that the anti-backup compression spring 8264 canproximally push the anti-backup cam tube 8268 and the anti-backuprelease lever 8248 to their retracted positions (FIG. 6).

In various embodiments, referring to FIGS. 1-3, the firing trigger 8034can be operably engaged to the linked rack 8200 in any suitable manner.With particular reference to FIGS. 2 and 3, the firing trigger 8034pivots about a firing trigger pin 8202 that is connected to the housing8154. An upper portion 8204 of the firing trigger 8034 moves distallyabout the firing trigger pin 8202 as the firing trigger 8034 isdepressed towards pistol grip 8036, stretching a proximally placedfiring trigger tension spring 8206 (FIG. 3) proximally connected betweenthe upper portion 8204 of the firing trigger 8034 and the housing 8154.The upper portion 8204 of the firing trigger 8034 engages the linkedrack 8200 during each firing trigger depression via a spring biased sidepawl mechanism 8210. When the firing trigger is released, the side pawlmechanism is disengaged from the linked rack 8200 and the firing triggercan be returned to an undepressed, or unfired, position. In use, aramped right-side track formed by a proximally and rightwardly facingbeveled surface 8284 in each of the links 8196 a-8196 d is engaged by aside pawl assembly 8285. In particular, a pawl slide 8270 (FIGS. 3 and4) has right and left lower guides 8272 that slide respectively in aleft track 8274 (FIG. 3) formed in the closure yoke 8266 below the rackchannel 8291 and a right track 8275 in a closure yoke rail 8276 thatparallels rack channel 8291 and is attached to a rack channel cover 8277that closes a rightwardly open portion of the rack channel 8291 in theclosure yoke 8266 that is distal to the travel of the pawl slide 8270.In FIGS. 3-5, a compression spring 8278 is attached between a hook 8279on a top proximal position on the closure yoke rail 8276 and a hook 8280on a distal right-side of the pawl slide 8270, which keeps the pawlslide 8270 drawn proximally into contact with the upper portion 8204 ofthe firing trigger 8034.

With particular reference to FIG. 3, a pawl block 8318 sits on the pawlslide 8270 pivoting about a vertical aft pin 8320 that passes through aleft proximal corner of pawl block 8318 and pawl slide 8270. A kick-outblock recess 8322 is formed on a distal portion of a top surface of theblock 8318 to receive a kick-out block 8324 pivotally pinned therein bya vertical pin 8326 whose bottom tip extends into a pawl spring recess8328 on a top surface of the pawl slide 8270. A pawl spring 8330 in thepawl spring recess 8328 extends to the right of the vertical front pin8326 urging the pawl block 8318 to rotate counterclockwise when viewedfrom above into engagement with the ramped right-side track 8282. Asmall coil spring 8332 in the kick-out block recess 8322 urges thekick-out block 8324 to rotate clockwise when viewed from above, itsproximal end urged into contact with a contoured lip 8334 formed in theclosure yoke 8266 above the rack channel 8291. As shown in FIG. 5, thestronger mechanical advantage of the pawl spring 8330 over the smallcoil spring 8332 means that the pawl block 8318 tends toward engagementwith the kick-out block 8324 rotated clockwise. In FIG. 3, as the firingtrigger 8034 is fully depressed and begins to be release, the kick-outblock 8324 encounters a ridge 8336 in the contoured lip 8334 as the pawlslide 8270 retracts, forcing the kick-out block 8324 to rotate clockwisewhen viewed from above and thereby kicking out the pawl block 8318 fromengagement with the linked rack 8200. The shape of the kick-out blockrecess 8322 stops the clockwise rotation of the kick-out block 8324 to aperpendicular orientation to the contoured lip 8334 maintaining thisdisengagement during the full retraction and thereby eliminating aratcheting noise.

In FIGS. 3, 4, 8, and 12, the surgical stapling and severing instrument8010 can include a manual retraction mechanism 8500 that provides for amanual release of the firing mechanism, manual retraction, and in oneversion (FIGS. 13-15) further performs automatic retraction at the endof full firing travel. Referring now to FIGS. 3 and 8, in particular, afront idler gear 8220 is engaged with a toothed upper, left surface 8222of the linked rack 8200 wherein the front idler gear 8220 also engagesan aft idler gear 8230 having a smaller right-side ratchet gear 8231.Both the front idler gear 8220 and aft idler gear 8230 are rotatablyconnected to the handle housing 8154 respectively on front idler axle8232 and aft idler axle 8234. Each end of the aft axle 8232 extendthrough the respective right and left housing half shells 8156, 8158 andare attached to the left and right indicator gauge wheels 8040, 8041and, since the aft axle 8234 is free spinning in the handle housing 8154and has a keyed engagement to the aft gear 8230, the indicator gaugewheels 8040, 8041 rotate with the aft gear 8230. The gear relationshipbetween the linked rack 8200, idler gear 8220 and aft gear 8230 may beadvantageously selected so that the toothed upper surface 8222 has toothdimensions that are suitably strong and that the aft gear 8230 makes nomore than one revolution during the full firing travel of the linkedtransmission firing mechanism 8150. In addition to gear mechanism 8502visually indicating the firing travel, or progress, the gear mechanism8502 can also be used to manual retract the knife. In variousembodiments, the smaller right-side ratchet gear 8231 of the aft idlergear 8230 extends into a hub 8506 of the manual retraction lever 8042,specifically aligned with a vertical longitudinally-aligned slot 8508(FIG. 8) bisecting the hub 8506. A lateral through hole 8510 of the hub8506 communicates with an upper recess 8512. A front portion 8514 isshaped to receive a proximally directed locking pawl 8516 that pivotsabout a rightward lateral pin 8518 formed in a distal end of the upperrecess 8512. An aft portion 8520 is shaped to receive an L-shaped springtab 8522 that urges the locking pawl 8516 downward into engagement withthe right-side smaller ratchet gear 8231. A hold-up structure 8524 (FIG.6) projects from the right half shell 8156 into the upper recess 8512holding up the locking pawl 8516 from engaging the smaller right-sideratchet gear 8231 when the manual retraction lever 8042 is down (FIG.10). A coil spring 8525 (FIG. 3) urges the manual retraction lever 8042down.

In use, as depicted in FIGS. 9 and 10, the combinationtension/compression spring 8184 may become disconnected with the linkedrack distally positioned. In FIGS. 11 and 12, as the manual retractionlever 8042 is raised, the locking pawl 8516 rotates clockwise and nolonger is held up by the hold-up structure 8524 and engages the smallerright-side ratcheting gear 8231, rotating the aft idler gear 8230clockwise when viewed from the left. Thus, the forward idler gear 8220responds counterclockwise retracting the linked rack 8200. In addition,a rightward curved ridge 8510 projects out from the hub 8506, sized tocontact and distally move the anti-backup release lever 8248 to releasethe anti-backup mechanism 8250 as the manual retraction lever 8042 isrotated.

In FIGS. 13-15, an automatic retraction mechanism 8600 for a surgicalstapling and severing instrument can incorporate automatic retraction atthe end of full firing travel into a front idler gear 8220 a having atooth 8602 that moves within a circular groove 8604 in a cam wheel 8606until encountering a blockage after nearly a full rotation correspondingto three firing strokes. In such circumstances, rightward ridge 8610 isrotated upward into contact a bottom cam recess 8612 to distally move ananti-backup release lever 8248 a. With particular reference to FIG. 13,the anti-backup release lever 8248 a includes the distal end 8254 thatoperates as previously described. The circular pin 8293 and pinreceptacle 8296 formed between right and left half shells 8156, 8158 isreceived through a generally rectangular aperture 8294 a formed in theanti-backup release lever 8248 a aft of the bottom cam 8192, thusallowing longitudinal translation as well as downward locking motion ofthe distal end 8254 of the anti-backup release lever 8248 a. In theright half shell 8156, a horizontal proximally open channel receives therightward aft pin near the proximal end of the anti-backup release lever8248 a.

In operation, before firing in FIGS. 13, 14, the linked rack 8200 andthe anti-backup cam tube 8268 are in a retracted position, locking theanti-backup mechanism 8250 as the anti-backup compression spring 8264proximally tips the anti-backup plate 8266. The automatic retractionmechanism 8600 is at an initial state with the anti-backup release lever8248 a retracted with link 8196 a in contact with the forward idler gear8220 a. The tooth 8602 is at a six o'clock position with full travel ofthe circular groove 8604 progressing counterclockwise thereof with therightward ridge 8610 just proximal to the tooth 8602. After one firingstroke, the linked rack 8200 has moved up one distal link 8196 b intocontact with the forward idler gear 8220 a. The tooth 8602 hasprogressed one third of a turn through the circular groove 8604 of theimmobile cam wheel 8606. After a second firing stroke, the linked rackhas moved up one more link 8196 c into contact with the forward idlergear 8220 a. The tooth 8602 has progressed two thirds of a turn throughthe circular groove 8604 of the immobile cam wheel 8606. After a thirdfiring stroke, the linked rack 8200 has moved up one distal link 8196 dinto contact with the forward idler gear 8220 a. The tooth 8602 hasprogressed fully around the circular groove 8604 into contact with theblockage, mentioned above, initiating counterclockwise rotation (whenviewed from the right) of the cam wheel 8606 bringing the rightwardridge into contact with the anti-backup release lever 8248 a. In FIG.15, the anti-backup release lever 8248 a has moved distally in responsethereto, locking the rightward front pin 8298 into the distally openstep structure 8299 and releasing the anti-backup mechanism 8250.Similar surgical stapling instruments are disclosed in U.S. Pat. No.7,083,075, which issued on Aug. 1, 2006, the entire disclosure of whichis incorporated by reference herein.

Referring to FIG. 16, the staple applying assembly 9012 of a surgicalstapling instrument 9010 accomplishes the functions of clamping ontotissue, driving staples and severing tissue by two distinct motionstransferred longitudinally down the shaft 9016 relative to a shaft frame9070. This shaft frame 9070 is proximally attached to a handle of asurgical stapling instrument and is coupled thereto for rotation about alongitudinal axis. An illustrative multi-stroke handle for the surgicalstapling and severing instrument is described in greater detail in theco-pending and co-owned U.S. patent application entitled SURGICALSTAPLING INSTRUMENT INCORPORATING A MULTISTROKE FIRING POSITIONINDICATOR AND RETRACTION MECHANISM, Ser. No. 10/374,026, the disclosureof which is hereby incorporated by reference in its entirety. Otherapplications consistent with the present invention may incorporate asingle firing stroke, such as described in co-pending and commonly ownedU.S. patent application SURGICAL STAPLING INSTRUMENT HAVING SEPARATEDISTINCT CLOSING AND FIRING SYSTEMS, Ser. No. 10/441,632, the disclosureof which is hereby incorporated by reference in its entirety.

With particular reference to FIG. 17, the distal end of the shaft frame9070 is attached to the staple channel 9018. The anvil 9022 has aproximal pivoting end 9072 that is pivotally received within a proximalend 9074 of the staple channel 9018, just distal to its engagement tothe shaft frame 9070. When the anvil 9022 is pivoted downwardly, theanvil 9022 moves a tissue contacting surface 9028 and forming pockets9026 toward an opposing staple cartridge, described in greater detailfurther below. The pivoting end 9072 of the anvil 9022 includes aclosure feature 9076 proximate but distal to its pivotal attachment withthe staple channel 9018. Thus, a closure tube 9078, whose distal endincludes a horseshoe aperture 9080 that engages this closure feature9076, selectively imparts an opening motion to the anvil 9022 duringproximal longitudinal motion and a closing motion to the anvil 9022during distal longitudinal motion of the closure tube 9078 sliding overthe shaft frame 9070 in response to a closure trigger, similar to theabove. The shaft frame 9070 encompasses and guides a firing motion fromthe handle through a longitudinally reciprocating, two-piece knife andfiring bar 9090. In particular, the shaft frame 9070 includes alongitudinal firing bar slot 9092 that receives a proximal portion ofthe two-piece knife and firing bar 9090, specifically a laminate taperedfiring bar 9094. It should be appreciated that the laminated taperedfiring bar 9094 may be substituted with a solid firing bar and/or anyother suitable materials.

An E-beam 9102 is the distal portion of the two-piece knife and firingbar 9090, which facilitates separate closure and firing as well asspacing of the anvil 9022 from the elongate staple channel 9018 duringfiring. With particular reference to FIGS. 17 and 19, in addition to anyattachment treatment such as brazing or an adhesive, the knife andfiring bar 9090 are formed of a female vertical attachment aperture 9104proximally formed in the E-beam 9102 that receives a corresponding maleattachment member 9106 distally presented by the laminated taperedfiring bar 9094, allowing each portion to be formed of a selectedmaterial and process suitable for their disparate functions (e.g.,strength, flexibility, friction). The E-beam 9102 may be advantageouslyformed of a material having suitable material properties for forming apair of top pins 9110, a pair of middle pins 9112 and a bottom pin orfoot 9114, as well as being able to acquire a sharp cutting edge 9116.In addition, integrally formed and proximally projecting top guide 9118and middle guide 9120 bracketing each vertical end of the cutting edge9116 further define a tissue staging area 9122 assisting in guidingtissue to the sharp cutting edge 9116 prior to being severed. The middleguide 9120 also serves to engage and fire the staple applying apparatus9012 by abutting a stepped central member 9124 of a wedge sled 9126(FIG. 20) that effects staple formation by the staple applying assembly9012, as described in greater detail below. Forming these features(e.g., top pins 9110, middle pins 9112, and bottom foot 9114) integrallywith the E-beam 9102 facilitates manufacturing at tighter tolerancesrelative to one another as compared to being assembled from a pluralityof parts, ensuring desired operation during firing and/or effectiveinteraction with various lockout features of the staple applyingassembly 9012.

In FIGS. 21 and 22, the staple applying assembly 9012 is shown open,with the E-beam 9102 fully retracted. During assembly, the lower foot9114 of the E-beam 9102 is dropped through a widened hole 9130 in thestaple channel 9018 and the E-beam 9102 is then advanced such that theE-beam 9102 slides distally along a lower track 9132 formed in thestaple channel 9018. In particular, the lower track 9132 includes anarrow slot 9133 that opens up as a widened slot 9134 on an undersurfaceof the staple channel 9018 to form an inverted T-shape in lateral crosssection, as depicted particularly in FIGS. 22 and 23, which communicateswith the widened hole 9130. Once assembled, the components proximallycoupled to the laminate tapered firing bar 9094 do not allow the lowerfoot 9114 to proximally travel again to the widened hole 9130 to permitdisengagement. Referring to FIG. 24, the laminate tapered firing bar9094 facilitates insertion of the staple applying assembly 9012 througha trocar. In particular, a more distal, downward projection 9136 raisesthe E-beam 9102 when fully retracted. This is accomplished by placementof the downward projection 9136 at a point where it cams upwardly on aproximal edge of the widened hole 9130 in the staple channel 9018.Referring now to FIG. 25, the laminate tapered firing bar 9094 alsoenhances operation of certain lockout features that may be incorporatedinto the staple channel 9018 by including a more proximal upwardprojection 9138 that is urged downwardly by the shaft frame 9070 duringan initial portion of the firing travel. In particular, a lateral bar9140 is defined between a pair of square apertures 9142 in the shaftframe 9070 (FIG. 17). A clip spring 9144 that encompasses the lateralbar 9140 downwardly urges a portion of the laminate tapered firing bar9094 projecting distally out of the longitudinal firing bar slot 9092,which ensures certain advantageous lockout features are engaged whenappropriate. This urging is more pronounced or confined solely to thatportion of the firing travel when the upward projection 9138 contactsthe clip spring 9144.

In FIGS. 21 and 22, the E-beam 9102 is retracted with the top pins 9110thereof residing within an anvil pocket 9150 near the pivoting proximalend of the anvil 9022. A downwardly open vertical anvil slot 9152 (FIG.16) laterally widens in the anvil 9022 into an anvil internal track 9154that captures the top pins 9110 of the E-beam 9102 as they distallyadvance during firing, as depicted in FIGS. 24 and 25, affirmativelyspacing the anvil 9022 from the staple channel 9018. Thus, with theE-beam 9102 retracted, the surgeon is able to repeatably open and closethe staple applying assembly 9012 until satisfied with the placement andorientation of tissue captured therein for stapling and severing, yetthe E-beam 9102 assists in proper positioning of tissue even for astaple applying assembly 9012 of reduced diameter and correspondinglyreduced rigidity. In FIGS. 16, 17, 20, 21, 23, and 29, the stapleapplying assembly 9012 is shown with the replaceable staple cartridge9020 that includes the wedge sled 9126. Longitudinally aligned andparallel plurality of downwardly open wedge slots 9202 (FIG. 23) receiverespective wedges 9204 integral to the wedge sled 9126. In FIGS. 23-25,the wedge sled 9126 thus cams upwardly a plurality of staple drivers9206 that are vertically slidable within staple driver recesses 9208. Inthis illustrative version, each staple driver 9206 includes two verticalprongs, each translating upwardly into a respective staple hole 9210, orcavity 9024, to upwardly force out and deform a staple 9023 restingthereupon against a staple forming surface 9214 (FIG. 25) of the anvil9022. A central firing recess 9216 (FIG. 17) defined within the staplecartridge 9020 proximate to the staple channel 9018 allows the passageof the bottom, horizontal portion 9218 (FIG. 20) of the wedge sled 9126as well as the middle pins 9112 of the E-beam 9102. Specifically, astaple cartridge tray 9220 (FIGS. 17, 23) attaches to and underlies apolymer staple cartridge body 9222 that has the staple driver recesses9208, staple holes 9210, and central firing recess 9216 formed therein.As staples 9023 are thus formed to either side, the sharp cutting edge9116 enters a vertical through slot 9230 passing through thelongitudinal axis of the staple cartridge 9020, excepting only a mostdistal end thereof.

Firing the staple applying assembly 9012 begins as depicted in FIG. 25with the two-piece knife and firing bar 9090 proximally drawn until thedownward projection 9136 cams the middle guide 9120 on the E-beam 9102upward and aft, allowing a new staple cartridge 9020 to be inserted intothe staple channel 9018 when the anvil 9022 is open as depicted in FIGS.16 and 21. In FIG. 26, the two-piece knife and firing bar 9090 has beendistally advanced a small distance, allowing the downward projection9136 to drop into the widened hole 9130 of the lower track 9132 underthe urging of the clip spring 9144 against the upward projection 9138 ofthe laminate tapered firing bar 9094. The middle guide 9120 preventsfurther downward rotation by resting upon the stepped central member9124 of the wedge sled 9126, thus maintaining the middle pin 9112 of theE-beam within the central firing recess 9216. In FIG. 27, the two-pieceknife and firing bar 9090 has been distally fired, advancing the wedgesled 9126 to cause formation of staples 9023 while severing tissue 9242clamped between the anvil 9022 and staple cartridge 9020 with the sharpcutting edge 9116. Thereafter, in FIG. 28, the two-piece knife andfiring bar 9090 is retracted, leaving the wedge sled 9126 distallypositioned. In FIG. 29, the middle pin 9112 is allowed to translate downinto a lockout recess 9240 formed in the staple channel 9018 (also seeFIGS. 22 and 25). Thus, the operator would receive a tactile indicationas the middle pin 9112 encounters the distal edge of the lockout recess9240 when the wedge sled 9126 (not shown in FIG. 29) is not proximallypositioned (i.e., missing staple cartridge 9020 or spent staplecartridge 9020). Similar surgical stapling instruments are disclosed inU.S. Pat. No. 7,380,696, which issued on Jun. 3, 2008, the entiredisclosure of which is incorporated by reference herein.

In various embodiments, turning now to FIGS. 30-38, a surgicalinstrument 12000 can comprise a handle 12010, a shaft 12020 extendingfrom the handle 12010, and an end effector 12040 removably attachable tothe shaft 12020, as described in greater detail further below. Thehandle 12010 can comprise a trigger 12014 which can be actuated to, one,close the end effector 12040 and, two, advance a firing member 12043distally through the end effector 12040. Although not illustrated inFIGS. 30-38, the handle 12010 can include any suitable drive trainconfigured to transfer and convert the rotational motion of the trigger12014 to linear motion of a firing member 12023 extending through theshaft 12010. In use, the trigger 12014 can be actuated toward a pistolgrip 12012 of the handle 12010 in order to advance the firing member12023 distally within the shaft 12020 along a longitudinal axis 12039and, when the shaft firing member 12023 is operably coupled with the endeffector firing member 12043, as discussed in greater detail furtherbelow, the distal movement of the shaft firing member 12023 can betransferred to the end effector firing member 12043. When the endeffector firing member 12043 is advanced distally, the end effectorfiring member 12043 can be configured to engage a first jaw 12040 aincluding an anvil and/or a second jaw 12040 b including a staplecartridge channel and move at least one of the first jaw 12040 a and thesecond jaw 12040 b toward the other. Further to the above, and referringprimarily to FIGS. 30-32, the end effector 12040 can be assembled to theshaft 12010 in a direction which is transverse to the longitudinal axis12039. For instance, the end effector 12040 can be assembled to theshaft 12010 in a direction which is perpendicular to the longitudinalaxis 12039, for example. In such circumstances, the end effector 12040can be moved toward the shaft 12010 such that the frame 12041 of the endeffector 12040 engages and connects to the frame 12021 and such that theproximal end 12044 of the firing member 12043 engages and couples to thedistal end 12024 of the firing member 12023. The shaft frame 12021 caninclude a channel 12022 defined therein which can be configured toslidably receive the shaft firing member 12023 and define thelongitudinal axis 12039. To align the end effector frame 12041 with theshaft frame 12021, in various embodiments, the proximal end 12045 of theend effector frame 12041 and the distal end 12025 of the shaft frame12021 can include co-operating dovetail features, for example, which canorient the end effector 12040 relative to the shaft 12020. The shaftframe 12021 can further include mounting apertures 12026 defined thereinwhich can be configured to receive mounting projections 12046 extendingfrom the end effector frame 12041. As a result of the co-operatingdovetail features of the ends 12025, 12045 and/or the mounting features12026, 12046, in various circumstances, can securely mount the endeffector 12040 to the shaft 12020. In various embodiments, the surgicalinstrument 12000 can further comprise a lock collar 12030 which can beconfigured to lock the end effector 12040 to the shaft 12020. Primarilyreferring now to FIGS. 34-36, the lock collar 12030 can be moved betweenan unlocked position (FIGS. 34 and 35) and a locked position (FIG. 36).When the lock collar 12030 is in its unlocked position, referring toFIG. 34, the end effector 12040 can be assembled to the shaft 12020.Once end effector 12040 has been engaged with the shaft 12020, the lockcollar 12030 can be slid over the interconnection between the endeffector 12040 and the shaft 12020 to lock the end effector 12040 inplace. More specifically, in at least one embodiment, the lock collar12030 can define an inner aperture 12031 which can be configured toclosely receive the outside perimeters of the end effector 12040 and theshaft 12020. In certain embodiments, the surgical instrument 12000 cancomprise a spring or biasing member configured to bias the lock collar12030 into its locked position. In such embodiments, a clinician canpull the lock collar 12030 proximally against the biasing force of thespring and, thereafter, release the lock collar 12030 and allow thespring to return the lock collar 12030 to its locked position.

Referring again to FIGS. 30-38, and primarily to FIGS. 32 and 33, thesurgical instrument 12000 can comprise an articulation joint 12050. Thearticulation joint 12050, in various embodiments, can be configured topermit a distal portion of the end effector 12040 to pivot about an axisdefined by the articulation joint 12050. In such and embodiment, the endeffector 12040 can comprise a proximal portion securely mounted to theshaft 12020 and the distal portion which can rotate relative to theproximal portion about the articulation joint 12050. In certainembodiments, the surgical instrument 12000 can comprise a lockconfigured to engage and disengage the distal portion of the endeffector 12040. For instance, the end effector 12040 can include an endeffector lock portion 12047 which can be pushed distally to lock thedistal portion of the end effector 12040 in position and/or pulledproximally to unlock the distal portion of the end effector 12040. Thesurgical instrument 12000 can further comprise a lock actuator 12060adjacent the handle 12010, for example, which can be pulled proximallyin order to pull the end effector lock portion 12047 proximally. In suchan embodiment, the lock actuator 12060 can be operably coupled with alock portion 12027 extending through the shaft 12020 which is operablycoupled, or operably couplable, to the end effector lock portion 12047.In at least one such embodiment, the proximal end 12048 of the endeffector lock portion 12047 can be assembled to the distal end 12028 ofthe lock portion 12027 when the end effector 12040 is assembled to theshaft 12020. In at least one such embodiment, the end effector lockportion 12047 can be assembled to the lock portion 12027 at the sametime that the end effector firing member 12043 is assembled to shaftfiring member 12023.

In various embodiments, as described above, a staple cartridge cancomprise a cartridge body including a plurality of staple cavitiesdefined therein. The cartridge body can comprise a deck and a top decksurface wherein each staple cavity can define an opening in the decksurface. As also described above, a staple can be positioned within eachstaple cavity such that the staples are stored within the cartridge bodyuntil they are ejected therefrom. Prior to being ejected from thecartridge body, in various embodiments, the staples can be containedwith the cartridge body such that the staples do not protrude above thedeck surface. As the staples are positioned below the deck surface, insuch embodiments, the possibility of the staples becoming damaged and/orprematurely contacting the targeted tissue can be reduced. In variouscircumstances, the staples can be moved between an unfired position inwhich they do not protrude from the cartridge body and a fired positionin which they have emerged from the cartridge body and can contact ananvil positioned opposite the staple cartridge. In various embodiments,the anvil, and/or the forming pockets defined within the anvil, can bepositioned a predetermined distance above the deck surface such that, asthe staples are being deployed from the cartridge body, the staples aredeformed to a predetermined formed height. In some circumstances, thethickness of the tissue captured between the anvil and the staplecartridge may vary and, as a result, thicker tissue may be capturedwithin certain staples while thinner tissue may be captured withincertain other staples. In either event, the clamping pressure, or force,applied to the tissue by the staples may vary from staple to staple orvary between a staple on one end of a staple row and a staple on theother end of the staple row, for example. In certain circumstances, thegap between the anvil and the staple cartridge deck can be controlledsuch that the staples apply a certain minimum clamping pressure withineach staple. In some such circumstances, however, significant variationof the clamping pressure within different staples may still exist.

In use, further to the above and referring primarily to FIG. 39, ananvil, such as anvil, 10060, for example, can be moved into a closedposition opposite the staple cartridge 10000. As described in greaterdetail below, the anvil 10060 can position tissue against the tissuethickness compensator 10020 and, in various embodiments, compress thetissue thickness compensator 10020 against the deck surface 10011 of thesupport portion 10010, for example. Once the anvil 10060 has beensuitably positioned, the staples 10030 can be deployed, as alsoillustrated in FIG. 39. In various embodiments, as mentioned above, thestaple-firing sled 10050 can be moved from the proximal end 10001 of thestaple cartridge 10000 toward the distal end 10002, as illustrated inFIG. 40. As the sled 10050 is advanced, the sled 10050 can contact thestaple drivers 10040 and lift the staple drivers 10040 upwardly withinthe staple cavities 10012. In at least one embodiment, the sled 10050and the staple drivers 10040 can each comprise one or more ramps, orinclined surfaces, which can co-operate to move the staple drivers 10040upwardly from their unfired positions. In at least one such embodiment,each staple driver 10040 can comprise at least one inclined surface andthe sled 10050 can comprise one or more inclined surfaces which can beconfigured such that the sled inclined surfaces can slide under thedriver inclined surface as the sled 10050 is advanced distally withinthe staple cartridge. As the staple drivers 10040 are lifted upwardlywithin their respective staple cavities 10012, the staple drivers 10040can lift the staples 10030 upwardly such that the staples 10030 canemerge from their staple cavities 10012 through openings in the stapledeck 10011 (FIG. 41). During an exemplary firing sequence, the sled10050 can contact a first staple 10030 and begin to lift the firststaple 10030 upwardly. As the sled 10050 is advanced further distally,the sled 10050 can begin to lift additional staples 10030, and any othersubsequent staples, in a sequential order. The sled 10050 can drive thestaples 10030 upwardly such that the legs 10032 of the staples contactthe opposing anvil, are deformed to a desired shape, and ejectedtherefrom the support portion 10010. In various circumstances, the sled10050 can move several staples upwardly at the same time as part of afiring sequence.

With reference to FIGS. 49-54, each staple 10030 can be deformed suchthat a compression zone 10039 is defined therein. For instance, eachstaple 10030 can comprise a base 10031 and one or more legs 10032extending from the base 10031 which, when deformed, can co-operativelydefine an area with the base 10031 within which the tissue T and thetissue thickness compensator 10020 can be captured. Within thecompression zone 10039, the tissue thickness compensator 10020 can applypressure to the tissue T and, in certain circumstances, assume differentcompressed heights depending on the thickness of the tissue T. In somecircumstances, the tissue thickness compensator 10020 can resilientlyfill gaps, or free spaces, present within the compression zones 10039defined by the staples 10030.

As discussed above, and referring to FIG. 41, the staple legs 10032 ofthe staples 10030 can extend above the deck surface 10011 of the supportportion 10010 when the staples 10030 are in their unfired positions. Invarious embodiments, the tips of the staple legs 10032, or any otherportion of the staple legs 10032, may not protrude through a toptissue-contacting surface 10021 of the tissue thickness compensator10020 when the staples 10030 are in their unfired positions. As thestaples 10030 are moved from their unfired positions to their firedpositions, the tips of the staple legs can protrude through thetissue-contacting surface. In various embodiments, the tips of thestaple legs 10032 can comprise sharp tips which can incise and penetratethe tissue thickness compensator 10020. In certain embodiments, thetissue thickness compensator 10020 can comprise a plurality of apertureswhich can be configured to receive the staple legs 10032 and allow thestaple legs 10032 to slide relative to the tissue thickness compensator10020. In certain embodiments, the support portion 10010 can furthercomprise a plurality of guides 10013 (FIG. 41) extending from the decksurface 10011. The guides 10013 can be positioned adjacent to the staplecavity openings in the deck surface 10011 such that the staple legs10032 can be at least partially supported by the guides 10013. Incertain embodiments, a guide 10013 can be positioned at a proximal endand/or a distal end of a staple cavity opening. In various embodiments,a first guide 10013 can be positioned at a first end of each staplecavity opening and a second guide 10013 can be positioned at a secondend of each staple cavity opening such that each first guide 10013 cansupport a first staple leg 10032 of a staple 10030 and each second guide10013 can support a second staple leg 10032 of the staple. In at leastone embodiment, referring to FIG. 41, each guide 10013 can comprise agroove or slot, such as groove 10016, for example, within which a stapleleg 10032 can be slidably received. In various embodiments, each guide10013 can comprise a cleat, protrusion, and/or spike that can extendfrom the deck surface 10011 and can extend into the tissue thicknesscompensator 10020. In at least one embodiment, as discussed in greaterdetail below, the cleats, protrusions, and/or spikes can reduce relativemovement between the tissue thickness compensator 10020 and the supportportion 10010. In certain embodiments, the tips of the staple legs 10032may be positioned within the guides 10013 and may not extend above thetop surfaces of the guides 10013 when the staples 10030 are in theirunfired position. In at least such embodiment, the guides 10013 candefine a guide height and the staples 10030 may not extend above thisguide height when they are in their unfired position.

In various embodiments, a tissue thickness compensator, such as tissuethickness compensator 10020, for example, can be comprised of a singlesheet of material. In at least one embodiment, a tissue thicknesscompensator can comprise a continuous sheet of material which can coverthe entire top deck surface 10011 of the support portion 10010 or,alternatively, cover less than the entire deck surface 10011. In certainembodiments, the sheet of material can cover the staple cavity openingsin the support portion 10010 while, in other embodiments, the sheet ofmaterial can comprise openings which can be aligned, or at leastpartially aligned, with the staple cavity openings. In variousembodiments, a tissue thickness compensator can be comprised of multiplelayers of material. In some embodiments, a tissue thickness compensatorcan comprise a compressible core and a wrap surrounding the compressiblecore.

In various embodiments, a tissue thickness compensator can comprise awrap for releasably holding a compressible core to the support portion10010. In at least one such embodiment, a staple cartridge can furthercomprise retainer clips which can be configured to inhibit the wrap, andthe compressible core, from prematurely detaching from the supportportion 10010. In certain embodiments, as described above, a tissuethickness compensator can be removably attached to the support portion10010 by the staples 10030. More particularly, as also described above,the legs of the staples 10030 can extend into the tissue thicknesscompensator 10020 when the staples 10030 are in their unfired positionand, as a result, releasably hold the tissue thickness compensator 10020to the support portion 10010. In at least one embodiment, the legs ofthe staples 10030 can be in contact with the sidewalls of theirrespective staple cavities 10012 wherein, owing to friction between thestaple legs 10032 and the sidewalls, the staples 10030 and the tissuethickness compensator 10020 can be retained in position until thestaples 10030 are deployed from the staple cartridge 10000. When thestaples 10030 are deployed, the tissue thickness compensator 10020 canbe captured within the staples 10030 and held against the stapled tissueT. When the anvil is thereafter moved into an open position to releasethe tissue T, the support portion 10010 can be moved away from thetissue thickness compensator 10020 which has been fastened to thetissue. In certain embodiments, an adhesive can be utilized to removablyhold the tissue thickness compensator 10020 to the support portion10010. In at least one embodiment, a two-part adhesive can be utilizedwherein, in at least one embodiment, a first part of the adhesive can beplaced on the deck surface 10011 and a second part of the adhesive canbe placed on the tissue thickness compensator 10020 such that, when thetissue thickness compensator 10020 is placed against the deck surface10011, the first part can contact the second part to active the adhesiveand detachably bond the tissue thickness compensator 10020 to thesupport portion 10010. In various embodiments, any other suitable meanscould be used to detachably retain the tissue thickness compensator tothe support portion of a staple cartridge.

In various embodiments, further to the above, the sled 10050 can beadvanced from a proximal end to a distal end to fully deploy all of thestaples 10030 contained within the staple cartridge 10000. In at leastone embodiment, referring now to FIG. 44, the sled 10050 can be advanceddistally within a longitudinal cavity within the support portion 10010by a firing member, or knife bar, 10052 of a surgical stapler. In use,the staple cartridge 10000 can be inserted into a staple cartridgechannel in a jaw of the surgical stapler and the firing member 10052 canbe advanced into contact with the sled 10050, as illustrated in FIG. 44.As the sled 10050 is advanced distally by the firing member 10052, thesled 10050 can contact the proximal-most staple driver, or drivers,10040 and fire, or eject, the staples 10030 from the cartridge body10010, as described above. As illustrated in FIG. 44, the firing member10052 can further comprise a cutting edge 10053 which can be advanceddistally through a knife slot in the support portion 10010 as thestaples 10030 are being fired. In various embodiments, a correspondingknife slot can extend through the anvil positioned opposite the staplecartridge 10000 such that, in at least one embodiment, the cutting edge10053 can extend between the anvil and the support portion 10010 andincise the tissue and the tissue thickness compensator positionedtherebetween. In various circumstances, the sled 10050 can be advanceddistally by the firing member 10052 until the sled 10050 reaches thedistal end of the staple cartridge 10000. At such point, the firingmember 10052 can be retracted proximally. In some embodiments, the sled10050 can be retracted proximally with the firing member 10052 but, invarious embodiments, the sled 10050 can be left behind in the distal end10002 of the staple cartridge 10000 when the firing member 10052 isretracted. Once the firing member 10052 has been sufficiently retracted,the anvil can be re-opened, the tissue thickness compensator 10020 canbe detached from the support portion 10010, and the remainingnon-implanted portion of the expended staple cartridge 10000, includingthe support portion 10010, can be removed from the staple cartridgechannel.

After the expended staple cartridge 10000 has been removed from thestaple cartridge channel, further to the above, a new staple cartridge10000, or any other suitable staple cartridge, can be inserted into thestaple cartridge channel. In various embodiments, further to the above,the staple cartridge channel, the firing member 10052, and/or the staplecartridge 10000 can comprise co-operating features which can prevent thefiring member 10052 from being advanced distally a second, orsubsequent, time without a new, or unfired, staple cartridge 10000positioned in the staple cartridge channel 10070. More particularly, asthe firing member 10052 is advanced into contact with the sled 10050and, when the sled 10050 is in its proximal unfired position, a supportnose of the firing member 10052 can be positioned on and/or over asupport ledge on the sled 10050 such that the firing member 10052 isheld in a sufficient upward position to prevent a lock, or beam, 10054extending from the firing member 10052 from dropping into a lock recessdefined within the staple cartridge channel. As the lock 10054 will notdrop into the lock recess, in such circumstances, the lock 10054 may notabut a distal sidewall of the lock recess as the firing member 10052 isadvanced. As the firing member 10052 pushes the sled 10050 distally, thefiring member 10052 can be supported in its upward firing position owingto the support nose resting on the support ledge. When the firing member10052 is retracted relative to the sled 10050, as discussed above, thefiring member 10052 can drop downwardly from its upward position as thesupport nose is no longer resting on the support ledge of the sled10050. In at least one such embodiment, the surgical stapler cancomprise a spring, and/or any other suitable biasing element, which canbe configured to bias the firing member 10052 into its downwardposition. Once the firing member 10052 has been completely retracted,the firing member 10052 cannot be advanced distally through the spentstaple cartridge 10000 once again. More particularly, the firing member10052 can't be held in its upper position by the sled 10050 as the sled10050, at this point in the operating sequence, has been left behind atthe distal end of the staple cartridge 10000. Thus, as mentioned above,in the event that the firing member 10052 is advanced once again withoutreplacing the staple cartridge, the lock beam 10054 will contact thesidewall 10057 of the lock recess which will prevent the firing member10052 from being advanced distally into the staple cartridge 10000 onceagain. Stated another way, once the spent staple cartridge 10000 hasbeen replaced with a new staple cartridge, the new staple cartridge willhave a proximally-positioned sled 10050 which can hold the firing member10052 in its upper position and allow the firing member 10052 to beadvanced distally once again.

As described above, the sled 10050 can be configured to move the stapledrivers 10040 between a first, unfired position and a second, firedposition in order to eject staples 10030 from the support portion 10010.In various embodiments, the staple drivers 10040 can be contained withinthe staple cavities 10012 after the staples 10030 have been ejected fromthe support portion 10010. In certain embodiments, the support portion10010 can comprise one or more retention features which can beconfigured to block the staple drivers 10040 from being ejected from, orfalling out of, the staple cavities 10012. In various other embodiments,the sled 10050 can be configured to eject the staple drivers 10040 fromthe support portion 10010 with the staples 10030. In at least one suchembodiment, the staple drivers 10040 can be comprised of a bioabsorbableand/or biocompatible material, such as Ultem, for example. In certainembodiments, the staple drivers can be attached to the staples 10030. Inat least one such embodiment, a staple driver can be molded over and/oraround the base of each staple 10030 such that the driver is integrallyformed with the staple. U.S. patent application Ser. No. 11/541,123,entitled SURGICAL STAPLES HAVING COMPRESSIBLE OR CRUSHABLE MEMBERS FORSECURING TISSUE THEREIN AND STAPLING INSTRUMENTS FOR DEPLOYING THE SAME,filed on Sep. 29, 2006, is hereby incorporated by reference in itsentirety.

In various circumstances, further to the above, a compressible tissuethickness compensator can move, twist, and/or deflect relative to theunderlying rigid support portion of a staple cartridge. In variousembodiments, the support portion, and/or any other suitable portion ofthe staple cartridge, can comprise one or more features configured tolimit relative movement between the tissue thickness compensator and thesupport portion. As described above, at least a portion of the staples10030 can extend above the deck surface 10011 of the support portion10010 wherein, in certain circumstances, lateral forces applied to atissue thickness compensator can be resisted by the staples 10030 and/orthe cleats 10013 extending from the support portion 10010, for example.In various circumstances, the staples 10030 may tilt and/or bend withinthe staple cavities 10012 while resisting the lateral movement of thetissue thickness compensator wherein, in various embodiments, the staplecavities 10012 and the staples 10030 can be sized and configured tomaintain the relative alignment between the legs 10032 of the staples10030 and the forming pockets in the opposing anvil 10060 such that thestaples 10000 are properly formed during the staple forming process. Invarious embodiments, the staples 10030 and/or the cleats 10013 can beconfigured to prevent or at least limit lateral distortion within thetissue thickness compensator 10020. In at least one such embodiment, thestaples 10030 and/or cleats 10013, for example, can be configured tostiffen, or limit the lateral and/or longitudinal movement of, a first,or tissue-contacting, surface of the tissue thickness compensatorrelative to a second, or bottom, surface. In various embodiments, astaple cartridge, and/or a staple cartridge channel in which the staplecartridge is positioned, can comprise at least one distortion minimizingmember which can extend upwardly to limit the lateral and/orlongitudinal movement, or distortion, of a tissue thickness compensator.A wrap at least partially surrounding a tissue thickness compensator, asdiscussed above, may also prevent, or at least limit, the lateral and/orlongitudinal movement, or distortion, of the tissue thicknesscompensator.

In various embodiments, a staple cartridge can comprise a plurality ofstaple cavities each containing a staple positioned therein wherein thestaple cavities can be arranged in a plurality of rows, and wherein ananvil positioned opposite the staple cartridge can comprise a pluralityof forming pockets which correspond to the staple cavities in the staplecartridge. Stated another way, the anvil can comprise a plurality offorming pocket rows wherein each forming pocket can be positionedopposite a staple cavity in the staple cartridge. In variousembodiments, each forming pocket can comprise two forming cupsconfigured to receive the staple legs 10032 of a staple 10030 whereineach forming cup is configured to receive a staple leg 10032 and form orcurl the staple leg 10032 toward the other staple leg 10032, forexample. In various circumstances, the legs 10032 may miss or notproperly enter into the forming cups and, as a result, the staple legs10032 may become malformed during the firing sequence. In variousembodiments described herein, an anvil can comprise an array, or grid,of forming pockets which are each configured to receive and form astaple leg. In at least one such embodiment, the array of formingpockets can comprise a quantity of forming pockets that exceeds thequantity of staples contained within the staple cartridge. In at leastone embodiment, a staple cartridge can comprise six longitudinal rows ofstaple cavities, for example, wherein the anvil can comprise six rows offorming pockets aligned with the six rows of staple cavities and, inaddition, forming pockets positioned intermediate the rows of formingpockets. For example, on one side of the anvil, the anvil can comprise afirst row of forming pockets which can be positioned over a first row ofstaple cavities, a second row of forming pockets which can be positionedover a second row of staple cavities that is adjacent to the first rowof staple cavities, and, in addition, a row of forming pocketspositioned intermediate the first row of forming pockets and the secondrow of forming pockets.

In various embodiments, as described above, an anvil can be moved froman open position to a closed position in order to compress tissueagainst the tissue thickness compensator of a staple cartridge, such astissue thickness compensator 10020, for example. In variouscircumstances, the tissue thickness compensator can be positionedadjacent to the support portion of the staple cartridge prior to thetissue thickness compensator being positioned relative to the tissue. Incertain embodiments, the tissue thickness compensator 10020 can be in aposition in which it abuts the support portion 10018 prior to the anvilbeing moved into its closed position. In certain other embodiments, thetissue thickness compensator 10020 can be in a position in which a gapis present between the tissue thickness compensator 10020 and thesupport portion 10018. In at least one such embodiment, the anvil candisplace the tissue and the tissue thickness compensator 10020downwardly until the tissue thickness compensator 10020 abuts thesupport portion 10018 wherein, at such point, the anvil can be movedinto is closed position and generate compression within the tissue. Inthe event that a surgeon is not satisfied with the positioning of thetissue between the anvil and the staple cartridge, the surgeon can openthe anvil, adjust the position of the anvil and the staple cartridge,and close the anvil once again. Owing to such positioning andre-positioning of the staple cartridge relative to the tissue, invarious circumstances, the distal end of the tissue thicknesscompensator 10020 may become dislodged from the support portion 10010,for example. In some such circumstances, the distal end of the tissuethickness compensator 10020 can contact the tissue and peel away from,or roll relative to, the support portion 10010. In various embodiments,as described in greater detail below, a staple cartridge can compriseone or more features configured to releasably retain a tissue thicknesscompensator to an underlying support portion of the staple cartridge

In various embodiments, referring now to FIG. 55, a staple cartridge10300 can comprise a support portion 10310, a tissue thicknesscompensator 10320 supported by the support portion 10310, and a distalend 10302 which includes a nose 10303 configured to releasably hold adistal end 10325 of the tissue thickness compensator 10320 in position.In at least one embodiment, the nose 10303 can comprise a slot 10305configured to receive the distal end 10325 of the tissue thicknesscompensator 10320. In various embodiments, the distal end 10325 can becompressed, or wedged, within the slot 10305 such that the distal end10325 can be held in place as the staple cartridge 10300 is positionedrelative to the tissue. In at least one such embodiment, the slot 10305can be oriented in a direction which is parallel, or at leastsubstantially parallel, to the deck surface 10311 of the support portion10310. In various embodiments, the slot 10305 can be horizontal withrespect to the deck surface 10311. In various other embodiments,referring now to FIG. 56, a staple cartridge 10400 can comprise asupport portion, a tissue thickness compensator 10420 supported bysupport portion, and a distal end 10402 which includes a nose 10403configured to releasably hold the distal end 10425 of the tissuethickness compensator 10420 in position. In at least one embodiment, thedistal end 10425 can comprise a projection extending therefrom and thenose 10403 can comprise a vertical slot 10405 configured to receive theprojection of the distal end 10425. In various embodiments, the distalend 10425, and/or the projection extending therefrom, can be compressed,or wedged, within the slot 10405 such that the distal end 10425 can beheld in place as the staple cartridge 10400 is positioned relative tothe tissue. In certain embodiments, the tissue thickness compensator10420 can comprise a slot, such as slot 10429, for example, which can beconfigured to receive at least a portion of the nose 10403 therein. Inat least one embodiment, the slot 10405 can be oriented in a directionwhich is perpendicular, or at least substantially perpendicular, to thedeck surface 10411 of the support portion. In various embodiments,referring now to FIG. 57, a staple cartridge 10500 can comprise asupport portion, a tissue thickness compensator 10520 supported by thesupport portion, and a distal end 10502 which includes a nose configuredto releasably hold the distal end 10525 of the tissue thicknesscompensator 10520 in position. In at least one embodiment, the nose cancomprise a vertical slot 10505 configured to receive the distal end10525 of the tissue thickness compensator 10520. In various embodiments,the distal end 10525 can be compressed, or wedged, within the slot 10505such that the distal end 10525 can be held in place as the staplecartridge 10500 is positioned relative to the tissue.

In various embodiments, referring again to FIG. 55, the tissue thicknesscompensator 10320 can comprise a top surface 10324 which can bepositioned above the top surface 10304 of the nose 10303. Anotherexemplary embodiment in which the top surface of a tissue thicknesscompensator is positioned above the nose of the staple cartridge isillustrated in FIG. 44, wherein the top surface 10721 of the tissuethickness compensator 10720 is positioned above the top surface 10004 ofthe nose 10003, for example. In use, referring once again to FIG. 55,tissue can slide over the top surface 10304 of the nose 10303 and, insome circumstance, the tissue can contact the distal end 10325 of thetissue thickness compensator 10320 and can apply a force to the tissuethickness compensator 10320 tending to peel the tissue thicknesscompensator 10320 away from the support portion 10310. In theembodiments described herein, this peel force can be resisted by theportion of the distal end 10325 wedged within the nose 10303. In anyevent, once the tissue has been suitably positioned relative to thestaple cartridge 13000, an anvil can be rotated into a closed positionto compress the tissue and the tissue thickness compensator 10320against the support portion 10310. In at least one such embodiment, theanvil can be rotated into a position in which the anvil contacts the topsurface 10304 of the nose 10303 and, as a result, the anvil can beprevented from rotating further. In various circumstances, owing to thetop surface 10324 of the tissue thickness compensator 10320 beingpositioned above the top surface 10304 of the nose 10303, the topsurface 10324 can be pushed downwardly toward the support portion 10310as the anvil is being closed and, in some circumstances, the top surface10324 can be pushed below the top surface 10304 of the nose 10303, forexample. After the staples contained within the staple cartridge 10300have been deployed and the tissue thickness compensator 10320 has beenincised, as described herein, the support portion 10310 and the nose10303 can be moved away from the tissue thickness compensator 10320 suchthat the distal end 10325 of the tissue thickness compensator 10320 canslide out of the slot 10305.

As described above, an anvil, such as anvil 10060, for example, can berotated into a closed position in which the anvil 10060 contacts the topnose surface 10004 of a staple cartridge, such as staple cartridge10000, for example. Once the anvil has reached its closed position, theamount in which a tissue thickness compensator, such as tissue thicknesscompensator 10020, for example, is compressed will depend on, amongother things, the uncompressed thickness, or height, of the tissuethickness compensator and the thickness of the tissue. Referring now toFIGS. 42 and 43, a tissue thickness compensator 10920 can comprise a topsurface which is flush, or at least substantially flush, with the topsurface 10004 of the nose 10003. In such embodiments, the top surface ofthe tissue thickness compensator 10920 can be pushed below the topsurface 10004 of the nose 10003. Referring now to FIGS. 47 and 48, atissue thickness compensator, such as tissue thickness compensator10820, for example, can comprise a top surface 10821 which is positionedbelow the top nose surface 10004 prior to the tissue thicknesscompensator 10820 being compressed by the tissue T and anvil 10060. Inthe circumstances where the tissue T is relatively thin, as illustratedin FIGS. 45 and 46, the tissue thickness compensator 10920 may undergorelatively little compression. Referring now to FIGS. 47 and 48, thetissue thickness compensator 10820 may undergo a larger compression whenthe tissue T is relatively thicker. In the circumstances where thetissue T has both thin sections and thicker sections, as illustrated inFIGS. 47 and 48, the tissue thickness compensator 10820 may becompressed a larger amount when it is positioned under the thickertissue T and a lesser amount when it is positioned under the thinnertissue T, for example. In this way, as described above, the tissuethickness compensator can compensate for different tissue thicknesses.

In various embodiments, referring now to FIGS. 58 and 59, a surgicalstapling instrument can comprise, one, a cartridge channel 16670configured to receive a staple cartridge 16600 and, two, an anvil 16660pivotably coupled to the cartridge channel 16670. The staple cartridge16600 can comprise a support portion 16610 and a tissue thicknesscompensator 16620 wherein a distal end 16625 of the tissue thicknesscompensator 16620 can be releasably held to the support portion 16610 bya nose 16603 at the distal end 16602 of the staple cartridge 16600. Inat least one embodiment, the nose 16603 can comprise a slot 16605 andcan be comprised of a flexible material. In use, referring primarily toFIG. 58, the nose 16603 can be flexed downwardly in order to expand theopening of slot 16605. In certain embodiments, the nose 16603 cancomprise notches or cut-outs 16606 which can be configured to permit thenose 16603 to flex downwardly. In any event, in various circumstances,the expanded opening of the slot 16605 can facilitate the insertion ofthe distal end 16625 of the tissue thickness compensator 16620 into theslot 16605. Once the tissue thickness compensator 16620 has beensuitably positioned, the nose 16603 can be released and, owing to theresiliency of the material comprising the nose 16603, the nose 16603 canreturn, or at least substantially return, to its unflexed condition andtrap the distal end 16625 of the tissue thickness compensator 16620against the deck surface 16611, as illustrated in FIG. 59. In use,similar to the above, the distal end 16625 can be pulled out of the slot16605 when the support portion 16610 is moved away from the stapledtissue. In various circumstances, the flexible nose 16603 can beconfigured to deflect as the tissue thickness compensator 16620 isdetached from the support portion 16610. In various embodiments,referring again to FIG. 59, the tissue thickness compensator 16620 cancomprise a top surface 16621 which is aligned, or at least substantiallyaligned, with a top surface 16604 of the nose 16603.

In various embodiments, referring now to FIGS. 60-61, a staplecartridge, such as staple cartridge 11400, for example, can comprise atissue thickness compensator 11420 removably attached to a supportportion 11410. In at least one embodiment, the staple cartridge 11400can comprise one or more retainer bars 11413 which can be configured tohold the longitudinal sides of the tissue thickness compensator 11420 tothe deck surface 11411. In at least one such embodiment, each retainerbar 11413 can comprise opposing arms 11418 which can define a channel11416 therebetween. In such embodiments, one of the arms 11418 can beconfigured to extend over the tissue thickness compensator 11420 and theother arm 11418 can be configured to extend under a lip 11419 extendingfrom the support portion 11410. Referring primarily to FIG. 60, thechannel 11416 of each retainer bar 11413 can be sized and configured toapply a compressive force to the longitudinal sides of the tissuethickness compensator 11420 prior to the staple cartridge 11400 beingused. During use, referring primarily to FIG. 61, the staple cartridge11400 can be positioned within a staple cartridge channel and, once thestaple cartridge 11400 has been suitably positioned, an anvil, such asanvil 11460, for example, can be moved into a position in which it cancompress the tissue thickness compensator 11420. Similar to the above,the thickness tissue compensator 11420, when compressed, can expandlaterally, or outwardly, and, as a result, detach the retainer bars11413 from the staple cartridge 11400. In certain other embodiments, theclosing of the anvil 11460 may not detach, or may not completely detach,the retainer bars 11413 from the staple cartridge. In at least one suchembodiment, the advancement of a firing bar, described above, throughthe staple cartridge 11400 can deploy the staples 10030 from the supportportion 11410 and, simultaneously, squeeze the anvil 11460 and thestaple cartridge 11400 closer together to apply a compressive force tothe tissue thickness compensator 11420 that is sufficient to cause thetissue thickness compensator 11420 to expand laterally and detach theretainer bars 11413 from the staple cartridge 11400. Once the retainerbars 11413 have been detached from the staple cartridge 11400, thesupport portion 11410 can be moved away from the implanted tissuethickness compensator 11420 and removed from the surgical site.

In various embodiments, further to the above, a staple cartridge cancomprise a plurality of fasteners configured to releasably hold a tissuethickness compensator to a support portion of the staple cartridge. Incertain embodiments, the support portion can comprise a plurality ofapertures defined in the deck surface, for example, wherein thefasteners can extend through the tissue thickness compensator and can bereleasably retained in the support portion apertures. In use, thefasteners can be progressively released from the support portion as thestaples are progressively ejected from the support portion. In at leastone such embodiment, the fasteners can be implanted with the tissuethickness compensator and, in at least one embodiment, the fasteners canbe comprised of at least one bioabsorbable material, for example. Incertain embodiments, the fasteners can detach from the support portionafter the tissue thickness compensator has been at least partiallyimplanted and as the support portion is moved away from the implantedtissue thickness compensator. In various embodiments, referring now toFIGS. 130-131, a staple cartridge, such as staple cartridge 11600, forexample, can comprise a tissue thickness compensator 11620 releasablymounted to a support portion 11610 by a plurality of fasteners 11613.Each fastener 11613 can comprise a first end 11618 embedded withinand/or otherwise engaged with the tissue thickness compensator 11620, asecond end 11618 engaged with the support portion 11610, and a connector11616 which connects the first end 11618 to the second end 11618. Invarious embodiments, the fasteners 11613 can extend through a knife slot11615 defined in the support portion 11610. In use, a firing member10052 can move a knife edge through the knife slot 11615 in the supportportion 11610 and incise the fasteners 11613 in order to release thetissue thickness compensator 11620 from the support portion 11610. In atleast one such embodiment, the firing bar 10052 can be advanced from aproximal end of the staple cartridge 11600 to a distal end of the staplecartridge 11600 in order to, one, advance the sled 10050 distally andprogressively fire the staples 10030, as discussed above, and, two,progressively incise and/or break the fasteners 11613 to progressivelyrelease the tissue thickness compensator 11620 from the support portion11610. In certain embodiments, similar to the above, the tissuethickness compensator 11620 can comprise a plurality of detachablesegments which can each be held to support portion 11610 by one or morefasteners 11613, for example. In the event that the firing member 10052is stopped intermediate the proximal end and the distal end of thestaple cartridge 11600, as illustrated in FIG. 130, the fasteners 11613can assist in holding the unimplanted portion of the tissue thicknesscompensator 11620 to the support portion 11610 after the anvil 11660 isopened and the support portion 11610 is moved away from the tissue T, asillustrated in FIG. 131. In various embodiments, further to the above,the cutting edge 10053 of the firing member 10052 can be configured toincise and/or break the fasteners 11613.

In various embodiments, referring now to FIG. 132, a staple cartridgecan comprise a tissue thickness compensator, such as tissue thicknesscompensator 15120, for example, which can comprise a plurality ofportions having different thicknesses. In at least one embodiment, thetissue thickness compensator 15120 can comprise a first, or inner,portion 15122 a which can have a first thickness, second, orintermediate, portions 15122 b extending from the first portion 15122 bwhich can each have a second thickness, and third, or outer, portions15122 c extending from the second portions 15122 b which can each have athird thickness. In at least one such embodiment, the third thicknesscan be thicker than the second thickness and the second thickness can bethicker than the first thickness, for example, although any suitablethicknesses could be utilized in various other embodiments. In variousembodiments, the portions 15122 a-15122 c of the tissue thicknesscompensator 15120 can comprise steps having different thickness. In atleast one embodiment, similar to the above, a staple cartridge cancomprise several rows of staples 10030 and a plurality of staple drivershaving different heights which can deform the staples 10030 to differentformed heights. Also similar to the above, the staple cartridge cancomprise first staple drivers 15140 a which can drive the staples 10030supported thereon to a first formed height, second staple drivers 15140b which can drive the staples 10030 supported thereon to a second formedheight, and third staple drivers which can drive the staples 10030supported thereon to a third formed height, wherein the first formedheight can be shorter than the second formed height and the secondformed height can be shorter than the third formed height, for example.In various embodiments, as illustrated in FIG. 132, each staple 10030can comprise the same, or substantially the same, unformed, or unfired,height. In certain other embodiments, referring now to FIG. 133, thefirst drivers 15140 a, the second drivers 15140 b, and/or the thirddrivers 15140 c can support staples having different unformed heights.In at least one such embodiment, the first staple drivers 15140 a cansupport staples 15130 a having a first unformed height, the secondstaple drivers 15140 b can support staples 15130 b having a secondunformed height, and the third staple drivers 15140 c can supportstaples 15130 c having a third unformed height, wherein the firstunformed height can be shorter than the second unformed height and thesecond unformed height can be shorter than the third unformed height,for example. In various embodiments, referring again to FIG. 133, thetips of the staples 15130 a, 15130 b, and/or 15130 c can lie, or atleast substantially lie, in the same plane while, in other embodiments,the tips of the staples 15130 a, 15130 b, and/or 15130 c may not lie insame plane.

In certain embodiments, referring now to FIG. 154, a staple cartridgecan include a tissue thickness compensator 15220 having a plurality ofportions having different thickness which can be implanted against thetissue T by the staples 15130 a, 15130 b, and 15130 c, as describedabove. In at least one embodiment, referring now to FIG. 155, thestaples 15130 a, 15130 b, and/or 15130 c can be deformed to differentformed heights wherein the first staples 15130 a can be formed to afirst formed height, the second staples 15130 b can be formed to asecond formed height, and the third staples 15130 c can be formed to athird formed height, and wherein the first formed height can be shorterthan the second formed height and the second formed height can beshorter than the third formed height, for example. Other embodiments areenvisioned in which the staples 15130 a, 15130 b, and 15130 c can beformed to any suitable formed heights and/or any relative formedheights.

As discussed above and referring to FIG. 134, a staple cartridge, suchas staple cartridge 10000, for example, can comprise a support portion10010 and a tissue thickness compensator 10020 wherein a plurality ofstaples 10030 can be at least partially stored in the support portion10010 and can extend into the tissue thickness compensator 10020 whenthe staples 10030 are in their unfired position. In various embodiments,the tips of the staples 10030 do not protrude from the tissue thicknesscompensator 10020 when the staples 10030 are in their unfired positions.As the staples 10030 are moved from their unfired positions to theirfired positions by the staple drivers 10040, as discussed above, thetips of the staples 10030 can penetrate through the tissue thicknesscompensator 10020 and/or penetrate through the upper layer, or skin,10022. In certain alternative embodiments, the tips of the staples 10030can protrude through the top surface of the tissue thickness compensator10020 and/or skin 10022 when the staples 10030 are in their unfiredposition. In either event, the staples 10030, as they extend upwardlyout of the support portion 10010 prior to being deployed, may tiltand/or deflect relative to the support portion, as also discussed above.

In various embodiments, referring now to FIG. 140, a staple cartridgecan comprise a tissue thickness compensator 13620 and a skin, or toplayer, 13621, for example. In at least one such embodiment, one or morepledgets, or retainers, 13622, for example, can be embedded in the skin13621. In certain embodiments, each retainer 13622 can comprise one ormore apertures 13629 defined therein which can be configured to receivethe staple legs 13032 of staples 13030 therein when the staples 13030are in their unfired position, as illustrated in FIG. 140. In use,further to the above, the staple legs 10032 can slide through theapertures 13629 when the staples 13030 are moved from their unfiredposition to their fired position until the bases 13031 of the staples13030 contact the tissue thickness compensator 13620 and compress atleast a portion of the tissue thickness compensator 13620 against thebottom surfaces of the pledgets 13622, for example. In variousembodiments, referring now to FIG. 135, a staple cartridge can comprisea tissue thickness compensator 13120 and a skin, or top layer, 13122,for example. In at least one such embodiment, the tissue thicknesscompensator 13120 can comprise conical bumps, projections, and/orprotrusions 13128, for example, which can extend upwardly from the topsurface 13121 of the tissue thickness compensator 13120. The projections13128 can be configured to receive and envelop the tips of the staplelegs 13032 of the staples 13030 when the staples 13030 are in theirunfired position, as illustrated in FIG. 135. The top layer 13122 canalso comprise conical bumps, projections, and/or protrusions 13129 whichcan be aligned, or at least substantially aligned, with the projections13128. In use, the staple legs 10032 can penetrate the projections 13128and 13129 and emerge from the tissue thickness compensator 13120. Invarious embodiments, referring now to FIG. 139, a staple cartridge cancomprise a tissue thickness compensator 13520 and a skin, or top layer,13522, for example. In at least one such embodiment, the skin 13522 cancomprise conical bumps, projections, and/or protrusions 13529, forexample, which can extend upwardly from the top surface 13521 of thetissue thickness compensator 13520. Similar to the above, theprojections 13529 can be configured to receive and envelop the tips ofthe staple legs 13032 of the staples 13030 when the staples 13030 are intheir unfired position, as illustrated in FIG. 139. In use, the staplelegs 10032 can penetrate the projections 13529 and emerge from the skin13522.

In various embodiments, referring now to FIG. 136, a staple cartridgecan comprise a tissue thickness compensator 13220 and a skin, or toplayer, 13222, for example. In at least one such embodiment, the tissuethickness compensator 13220 can comprise conical dimples and/or recesses13128, for example, which can extend downwardly into the top surface13221 of the tissue thickness compensator 13220. In various embodiments,the tips of the staple legs 13032 can extend through the recesses 13128when the staples 13030 are in their unfired position, as illustrated inFIG. 136. In at least one embodiment, the top layer 13222 can alsocomprise conical dimples and/or recesses 13229 which can be aligned, orat least substantially aligned, with the recesses 13228. In variousembodiments, referring now to FIG. 137, a staple cartridge can comprisea tissue thickness compensator 13320 and a skin, or top layer, 13322,for example. In at least one such embodiment, the skin 13320 cancomprise thick portions 13329 which can extend downwardly into the topsurface 13321 of the tissue thickness compensator 13320. In variouscircumstances, the thick portions 13329 can be configured to receive atleast a portion of the staple legs 13032 of the staples 13030 thereinwhen the staples 13030 are in their unfired position, as illustrated inFIG. 137. In such embodiments, the thick portions 13329 can hold thestaple legs 13032 in position such that the legs 13032 are aligned, orat least substantially aligned, with the staple-forming pockets of ananvil positioned opposite the tissue thickness compensator 13320. Invarious embodiments, referring now to FIG. 138, a staple cartridge cancomprise a tissue thickness compensator 13420 and a skin, or top layer,13422, for example. In at least one such embodiment, the skin 13422 cancomprise thick portions 13429 which can extend upwardly from the topsurface 13421 of the tissue thickness compensator 13420. In variouscircumstances, the thick portions 13429 can be configured to receive atleast a portion of the staple legs 13032 of the staples 13030 thereinwhen the staples 13030 are in their unfired position, as illustrated inFIG. 138. In such embodiments, the thick portions 13429 can hold thestaple legs 13032 in position such that the legs 13032 are aligned, orat least substantially aligned, with the staple-forming pockets of ananvil positioned opposite the tissue thickness compensator 13420.

In various embodiments, referring now to FIGS. 141 and 142, a staplecartridge can comprise a tissue thickness compensator 13720 and a skin,or top layer, 13721, for example. In at least one such embodiment, thetissue thickness compensator 13720 can comprise pyramidal and/or steppedbumps, projections, and/or protrusions 13728, for example, which canextend upwardly from the top surface 13721 of the tissue thicknesscompensator 13720. The projections 13728 can be configured to receiveand envelop the tips of the staple legs 13032 of the staples 13030 whenthe staples 13030 are in their unfired position, as illustrated in FIG.142. Similarly, the top layer 13721 can comprise pyramidal and/orstepped bumps, projections, and/or protrusions 13729 which can bealigned, or at least substantially aligned, with the projections 13728.In various embodiments, the skin 13721 can further comprise one or moreteeth 13727 extending upwardly from the projections 13729 which can beconfigured to engage tissue positioned against the top layer 13721 andprevent, or at least limit, relative lateral and/or longitudinalmovement between the tissue, the top layer 13721, and/or the tips of thestaple legs 13032. In use, the staple legs 13032 can penetrate theprojections 13728 and 13729 and emerge from the tissue thicknesscompensator 13720 when the staples 13030 are moved from their unfiredpositions to their fired positions. In various embodiments, referringnow to FIGS. 143 and 144, a staple cartridge can comprise a tissuethickness compensator 13820 and a skin, or top layer, 13821, forexample. In at least one such embodiment, the tissue thicknesscompensator 13820 can comprise pyramidal and/or stepped bumps,projections, and/or protrusions 13828, for example, which can extendupwardly from the top surface 13821 of the tissue thickness compensator13820. The projections 13828 can be configured to receive and envelopthe tips of the staple legs 13032 of the staples 13030 when the staples13030 are in their unfired position, as illustrated in FIG. 144.Similarly, the top layer 13821 can comprise pyramidal and/or steppedbumps, projections, and/or protrusions 13829 which can be aligned, or atleast substantially aligned, with the projections 13828. In variousembodiments, the top layer 13821 can further comprise one or more teeth13827 extending downwardly into the tissue thickness compensator 13820which can be configured to prevent, or at least limit, relative lateraland/or longitudinal movement between the top layer 13821 and the tissuethickness compensator 13820, for example. In use, the staple legs 10032can penetrate the projections 13828 and 13829 and emerge from the tissuethickness compensator 13820 when the staples 13030 are moved from theirunfired positions and their fired positions.

In various embodiments, referring now to FIG. 145, a staple cartridgecan comprise a tissue thickness compensator, such as tissue thicknesscompensator 13920, for example, which can include ridges 13923 andvalleys 13924 defined therein wherein, in at least one embodiment, thevalleys 13924 can be defined between the ridges 13923. In variousembodiments, each ridge 13923 can comprise the same height,substantially the same height, or different heights. Similarly, eachvalley 13924 can comprise the same depth, substantially the same depth,or different depths. In various embodiments, a plurality of staples13030 can be at least partially stored within the tissue thicknesscompensator 13920 such that the tips of the staples 13030 can bepositioned within the ridges 13923. In at least one such embodiment, thestaple legs 13032 of the staples 13030 may not protrude from the tissuethickness compensator 13920 and/or a skin, or top layer, 13921 attachedto the tissue thickness compensator 13920, for example, when the staples13030 are stored in their unfired position. In various embodiments, theridges 13923 and/or the valleys 13924 can extend laterally across thestaple cartridge. In at least one such embodiment, the staple cartridgecan comprise a longitudinal knife slot wherein the ridges 13923 and thevalleys 13924 can extend in a direction which is transverse and/orperpendicular to the knife slot. In various circumstances, the ridges13923 can be configured to hold the tips of the staple legs 13032 inposition until the staples 13030 are moved from their unfired positioninto their fired position. In various embodiments, referring now to FIG.146, a tissue thickness compensator, and/or a skin covering a tissuethickness compensator, can comprise longitudinal ridges and/or valleys.In at least one such embodiment, a tissue thickness compensator cancomprise a top surface defined by ridges 14023 and valleys 14024,wherein the valleys 14024 can be defined between the ridges 14023, forexample. In various embodiments, the tissue thickness compensator cancomprise a skin 14021 which can include a plurality of apertures 14029defined therein which can each be configured to receive a staple leg13032. In certain embodiments, the apertures 14029 can be defined in theridges 14023 wherein the tips of the staple legs 13032 may be positionedbelow the peaks 14028 of the ridges 14029, positioned flush with thepeaks 14028, and/or positioned above the peaks 14028. In certainembodiments, in addition to or in lieu of the above, the apertures 14029can be defined in the valleys 14024, for example. In certainembodiments, each aperture can be surrounded, or at least partiallysurrounded, by an embossment, for example, which can strengthen the skinand/or tissue thickness compensator surrounding the apertures. In anyevent, further to the above, the skin 14021 can be attached to a tissuethickness compensator in any suitable manner, including using at leastone adhesive, for example.

In various embodiments, referring now to FIG. 148, a disposable loadingunit 15900, for example, can comprise an anvil 15960 and a staplecartridge channel 15970 wherein the staple cartridge channel 15970 canrotate relative to the anvil 15960. In at least one such embodiment, theanvil 15960 may not be able to rotate. In certain embodiments, tissuecan be positioned between the anvil 15960 and the staple cartridgechannel 15970 and, thereafter, the staple cartridge channel 15970 can berotated toward the tissue to clamp the tissue against the anvil. In atleast one such embodiment, the disposable loading unit 15900 can furthercomprise a tissue thickness compensator 15920 which can be configured tocontact the tissue.

In various embodiments, referring now to FIGS. 149-151, a disposableloading unit 12900 can comprise a loading assembly including a bottomportion 12922 which can be removably attached to the support portion12610, a top portion 12990 which can be removably attached to the anvil12560, and a flexible joint 12991 connecting the bottom portion 12922and the top portion 12990. Similar to the above, a longitudinalretention rail 12825 can extend downwardly from the bottom portion 12922and into the knife slot 12615 defined in the support portion 12610 suchthat the bottom portion 12922 can be releasably retained to the supportportion 12610. Similarly, a longitudinal retention rail 12995 can extendupwardly from the top portion 12990 into a knife slot defined in theanvil 12560 such that the top portion 12990 can be releasably retainedto the anvil 12560. As illustrated in FIGS. 150 and 151, a tissuethickness compensator 12620 can be mounted to the bottom portion 12922of the loading assembly wherein, in order to position the tissuethickness compensator 12620 relative to the support portion 12610, aclinician could flex the top portion 12990 and the bottom portion 12922toward one another, position the loading assembly between the anvil12560 and the support portion 12610, and release the flexed loadingassembly such that it can resiliently expand and bias the top portion12990 against the anvil 12560 and the bottom portion 12922 against thesupport portion 12610.

In various embodiments, referring now to FIG. 152, a staple cartridge,such as staple cartridge 14900, for example, can comprise a supportportion 14910 and, in addition, a tissue thickness compensator 14920positioned against the support portion 14910. Similar to the above, thesupport portion 14910 can comprise staple drivers which can be liftedupwardly by a staple-deploying sled in order to lift staples, such asstaples 10030, for example, at least partially positioned within thesupport portion 14910 toward an anvil, such as anvil 10060, for example,positioned opposite the staple cartridge 14900. In certain embodiments,the support portion 14910 can comprise six rows of staple cavities, suchas two outer rows of staple cavities, two inner rows of staple cavities,and two intermediate rows of staple cavities positioned intermediate theinner rows and the outer rows, for example, wherein the anvil 10060 cancomprise six rows of forming pockets 10062 aligned, or at leastsubstantially aligned, with the staple cavities. In various embodiments,the inner rows of staple cavities can include staple drivers 14940 apositioned therein, the intermediate rows of staple cavities can includestaple drivers 14940 b positioned therein, and the outer rows of staplecavities can include staple drivers 14940 c positioned therein, whereineach of the staple drivers 14940 a can include a cradle 14949 aconfigured to support a staple 10030, wherein each of the staple drivers14940 b can include a cradle 14949 b configured to support a staple10030, and wherein each of the staple drivers 14940 c can include acradle 14949 c configured to support a staple 10030. In their unfiredpositions, i.e., when the staple drivers 14940 a-14940 c are sitting ondriver supports 14926 which extend underneath the support portion 14910,the cradles 14949 a of the staple drivers 14940 a can be positionedcloser to the anvil 10060 than the cradles 14949 b of the staple drivers14940 b and the cradles 14949 c of the staple drivers 14940 c. In such aposition, a first forming distance can be defined between the cradles14949 a and the forming pockets 10062 positioned over the cradles 14949a, a second forming distance can be defined between the cradles 14949 band the forming pockets 10062 positioned over the cradles 14949 b, and athird forming distance can be defined between the cradles 14949 c andthe forming pockets 10062 positioned over the cradles 14949 c, wherein,in various embodiments, the first forming distance can be shorter thanthe second forming distance and the second forming distance can beshorter than the third forming distance, for example. When the stapledrivers 14940 a-14940 c are moved from their unfired positions (FIG.152) to their fired positions, each staple driver 14940 a-14940 c can bemoved upwardly an equal, or an at least substantially equal, distancetoward the anvil 10060 by the staple-deploying sled such that the firstdrivers 14940 a drive their respective staples 10030 to a first formedheight, the second drivers 14940 b drive their respective staples 10030to a second formed height, and the third drivers 14940 c drive theirrespective staples 10030 to a third formed height, wherein the firstformed height can be shorter than the second formed height and thesecond formed height can be shorter than the third formed height, forexample. Various other embodiments are envisioned in which the firststaple drivers 14940 a are displaced upwardly a first distance, thesecond staple drivers 14940 b are displaced upwardly a second distance,and the third staple drivers 14940 c are displaced upwardly a thirddistance, wherein one or more of the first distance, the seconddistance, and the third distance can be different.

In various embodiments, referring again to FIG. 152, the deck surface14911 of the support portion 14910 can vary in height with respect tothe tissue-contacting surface 10061 of the anvil 10060. In certainembodiments, this height variation can occur laterally and, in at leastone embodiment, the height of the deck surface 14911 surrounding theinner rows of staple cavities can be higher than the deck surface 14911surrounding the outer rows of staple cavities, for example. In variousembodiments, the bottom surface 14922 of the tissue thicknesscompensator 14920 can be configured to parallel, or at leastsubstantially parallel, the deck surface 14911 of the support portion14910. Further to the above, the tissue thickness compensator 14920 canalso vary in thickness wherein, in at least one embodiment, the top, ortissue-contacting, surface 14921 of the tissue thickness compensator14920 can slope inwardly from the outside or lateral edges thereof. Inat least one such embodiment, as a result of the above, the tissuethickness compensator 14920 can be thinner in a region positioned overthe inner rows of staple cavities and thicker in a region positionedover the outer rows of staple cavities, for example. In variousembodiments, referring now to FIG. 153, the deck surface of a supportportion 15010 can comprise a stepped deck surface, for example, whereinthe highest steps of the stepped surface can surround the inner rows ofstaple cavities and the lowest steps of the stepped surface can surroundthe outer rows of staple cavities, for example. In at least one suchembodiment, steps having an intermediate height can surround theintermediate rows of staple cavities. In certain embodiments, a tissuethickness compensator, such as tissue thickness compensator 15020, forexample, can comprise a bottom surface which can parallel and abut thedeck surface of the support portion 15010. In at least one embodiment,the top, or tissue-contacting, surface 15021 of the tissue thicknesscompensator can comprise an arcuate, parabolic, and/or curved surface,for example, which, in at least one such embodiment, can extend from afirst lateral side of the tissue thickness compensator 15020 to a secondlateral side of the tissue thickness compensator 15020 with an apexaligned, or at least substantially aligned, with the center of thestaple cartridge 15000, for example.

In various embodiments, further to the above, a staple-firing sled 10050of a staple cartridge 10000 can be moved from a proximal end of thestaple cartridge 10000 toward a distal end 10002 of the staplecartridge, as illustrated in FIGS. 161 and 162, by a firing member,illustrated elsewhere. As the sled 10050 is advanced, the sled 10050 cancontact the staple drivers 10040 and lift the staple drivers 10040upwardly within the staple cavities 10012 defined in a cartridge body10010 of the staple cartridge 10000. In at least one embodiment, thesled 10050 and the staple drivers 10040 can each comprise one or moreramps, or inclined surfaces, which can co-operate to move the stapledrivers 10040, and the staples supported thereon, upwardly from theirunfired positions. The staple cartridge 10000 can further comprise a pan10027, for example, which can at least partially surround the bottom ofthe cartridge body 10010 and at least partially contain the stapledrivers 10040 within the cartridge body 10010. The cartridge body 10010can further comprise a longitudinal slot 10016 defined therein which canbe configured to at least partially receive the firing member as itpasses through the staple cartridge 10000.

Turning now to FIG. 163, the staples contained within the staplecartridge body 10010 can be fired sequentially between a proximal end10001 and a distal end 10002 of the staple cartridge 10000. In variousembodiments, the staple cartridge 10000 can comprise staple drivers10040 a, 10040 b, and 10040 c, for example, which can fire the staplesin a predetermined manner. For instance, the staple cartridge 10000 cancomprise a proximal driver 10040 c positioned on a first side of thelongitudinal slot 10016 and a second proximal driver 10040 c positionedon a second, or opposite, side of the slot 10016. Each driver 10040 ccan be configured to fire two staples, i.e., the two proximal-moststaples, simultaneously. Such staples are positioned in the staplecavities designated 10012 c. In fact, of the two staple cavitiesdesignated 10012 c on each side of the slot 10016, such staple cavities10012 c can comprise a distal staple cavity designated 10013 c and aproximal staple cavity 10014 c. The reader will appreciate that thestaple cavity 10013 c is positioned in a different staple row than thestaple cavity 10014 c. In fact, the staple cavities 10013 c and 10014 cmay be located in the two innermost rows of staples with the third,outermost, staple row not having a staple which is fired by a driver10040 c. Furthermore, the staple cartridge 10000 can comprise anintermediate driver 10040 b positioned on a first side of thelongitudinal slot 10016 and a second intermediate driver 10040 bpositioned on a second, or opposite, side of the slot 10016. Each driver10040 b can be configured to fire three staples simultaneously. Suchstaples are positioned in the staple cavities designated 10012 b. Infact, of the three staple cavities designated 10012 b on each side ofthe slot 10016, such staple cavities 10012 b can comprise a distalstaple cavity designated 10013 b, an intermediate staple cavity 10014 b,and a distal staple cavity 10015 b. The reader will also appreciate thatthe staple cavities 10013 b, 10014 b, and 10015 b are all positioned indifferent staple rows. In addition, the staple cartridge 10000 cancomprise a distal driver 10040 a positioned on a first side of thelongitudinal slot 10015 and a second distal driver 10040 a positioned ona second, or opposite, side of the slot 10015. Each driver 10040 a canbe configured to fire four staples simultaneously. Such staples arepositioned in the staple cavities designated 10012 a. In fact, of thefour staple cavities designated 10012 a on each side of the slot 10016,such staple cavities 10012 a can comprise two distal staple cavitiesdesignated 10013 a, an intermediate staple cavity 10014 a, and a distalstaple cavity 10015 a. The reader will also appreciate that the staplecavities 10013 a, 10014 a, and 10015 a are all positioned in an arrayextending across all three staple rows on a side of the longitudinalslot 10016. In fact, the distal-most staples positioned within thedistal-most cavities 10013 a within the cartridge body 10010 arepositioned in the inner and outer staple rows and extend distally withrespect to the distal-most staple cavity 10014 a in the intermediate rowpositioned between the inner row and outer row of staple cavities. Whileonly a few staple drivers 10040 a, 10040 b, and 10040 c are discussedabove, the staple cartridge 10000 can comprise any suitable number ofstaple drivers to eject the staples from the staple cavities. Suchstaple drivers can eject two, three, four, and/or more staplessimultaneously. With particular reference to FIG. 18, a staple cartridgecan comprise one or more staple drivers 41040 a, for example, configuredto support two staples thereon, one or more drivers 41040 b, forexample, configured to support three staples thereon, and/or one or morestaple drivers 41040 c configured to support four staples thereon. Invarious embodiments, the last, or distal-most, drivers contained withina cartridge can comprise drivers 41040 c which can include two distalsupport cradles 41041 c which can hold the last staples in a stapleline. For instance, the drivers 41040 a-c support staples in six staplelines and drivers 41040 c support the last staples in four of thoselines. Such staples can be aligned, or at least substantially aligned,along an axis which is perpendicular to a cut path which extends along alongitudinal axis. Such staples, owing to their arrangement, can providevarious hemostatic advantages. The last staples in the other two staplelines can be supported by cradles 41041 b.

In various embodiments, a staple cartridge for a surgical stapler caninclude a layer, such as a tissue thickness compensator and/or abuttress material, for example, arranged on a staple deck of a staplecartridge. In use, the layer and patient tissue can be captured bystaples when the staples are fired. Then, the layer can be separatedfrom the surgical stapler and can remain in the patient when the stapleris removed from the patient. In certain embodiments, a distal end of thelayer can be attached to the staple cartridge to stabilize the layerrelative to the staple cartridge while the staple cartridge and thelayer are being positioned relative to patient tissue.

In certain embodiments in which a distal end of the layer is attached tothe staple cartridge, the staple cartridge can include adistally-arranged cutting blade that cuts the layer free from the distalend that is attached to the staple cartridge. FIGS. 81A-83 illustrate astaple cartridge assembly 2300 that includes a staple cartridge 2330 anda distal cutting blade 2324 arranged in a distal cavity 2332 of thestaple cartridge 2330. As described in greater detail below, the distalcutting blade 2324 can be moved from an undeployed position within thedistal cavity 2332 to a deployed positioned in which the cutting blade2324 extends out of the distal cavity 2332 to sever a distal end portion2316 of a layer 2306 arranged on the staple cartridge.

Referring to FIGS. 82 and 83, in various embodiments, the distal portion2316 of the layer 2306 can be attached to the staple cartridge 2300 bybeing captured between the staple cartridge 2300 and a panel 2310extending proximally from a nose 2308 of the staple cartridge assembly2300. In certain embodiments, the layer 2306 can be captured by beingcompressed between the staple cartridge 2330 and the panel 2310. Putdifferently, a gap between the staple cartridge 2330 and the panel 2310can be smaller than a thickness of the distal portion 2316 of the layer2306 positioned in the gap so that the distal portion 2316 is compressedbetween the staple cartridge 2330 and the panel 2310. In certainembodiments, referring to FIGS. 82 and 83, the distal portion 2316 ofthe layer 2306 can include one or more apertures 2320. One or more pegs2318 can extend from the panel 2308 and pass through the apertures 2320to capture the distal portion 2316 of the layer 2306. In certainembodiments, the distal portion 2316 of the layer 2306 can be attachedto the staple cartridge 2330 by adhesives, welding, and/or heat staking,for example.

The distal cutting blade 2324 that severs the distal portion 2316 of thelayer 2306 from the remainder of the layer 2306 can be arranged in adistal cavity 2332 of the staple cartridge 2330. The distal cavity 2332and the distal cutting blade 2324 can be positioned such that the distalcutting blade 2324 can sever the distal portion 2316 of the layer 2306at a proximal location relative to a location where the distal portion2316 is attached to the staple cartridge 2330. For example, referring toFIGS. 82 and 83, the distal cutting blade 2324 can sever the distalportion 2316 of the layer 2306 at a proximal location relative to thepegs 2318 and apertures 2320 that attach the distal portion 2316 to thestaple cartridge 2330. As a result, when the distal cutting blade 2324severs the distal portion 2316 of the layer 2306, the remainder of thelayer 2306 can be released from the staple cartridge.

The distal cutting blade 2324 can include a cam 2322 that can push thedistal cutting blade 2324 out of the distal cavity 2332. The cam 2322can engage rails and/or channels 2334 in the distal cavity 2332 that canconstrain the movement of the cam 2322 and the distal cutting blade 2324to a particular direction as the blade 2324 extends out of the distalcavity 2332. The rails and/or channels 2334 are illustrated in FIGS. 82and 83 as being perpendicular to the staple deck 2302 of the staplecartridge 2330. In such an arrangement, when moved from an undeployedposition (shown in FIG. 82) to a deployed position (shown in FIG. 83),the distal cutting blade 2324 can extend from the distal cavity 2332 ina direction that is perpendicular to the staple deck 2302 of the staplecartridge 2330. In various embodiments, the rails and/or channels 2334can be arranged at any suitable angle relative to the staple deck 2302of the staple cartridge 2330. For example, the rails or channels 2334can be arranged at a 30° angle relative to the staple deck 2302 of thestaple cartridge 2330 such that the distal cutting blade 2324 extendsout of the distal cavity 2322 partially in a distal direction that is30° from perpendicular relative to the staple deck 2302 of the staplecartridge 2330.

To deploy the distal cutting blade, the cam 2322 can be pushed by afiring member 2326. The firing member 2326 can be arranged in a slot inthe staple cartridge 2330, such as the knife slot 2304, for example. Thefiring member 2326 can include cam surfaces 2328 and 2329 that canengage the cam 2322 to displace the cam 2322 and the distal cuttingblade 2324 towards the layer 2306. The firing member 2326 can movedistally relative to the cam 2322 and the distal cutting blade 2324 froman unactuated position to an actuated position to deploy the cuttingblade 2324 and sever the distal portion 2316 of the layer 2306. FIG. 82illustrates the firing member 2326 in an unactuated position in whichthe cam surfaces 2328 and 2329 have not engaged the cam 2322. In variousembodiments, one or both of the surfaces 2328 and 2329 of the firingmember 2326 can be in contact the cam in an unactuated position so longas the distal cutting blade 2324 is not pushed out of the distal cavity2332. As the firing member 2326 moves distally to an actuated positionillustrated in FIG. 83, the cam surfaces 2328 of the firing member 2326engage the cam 2322 to progressively push the cam 2322 and the distalcutting blade 2324 to a deployed position such that the distal cuttingblade severs the distal portion 2316 of the layer 2306.

As described above, the cam 2322 can engage rails and/or channels 2334in the distal cavity 2332. Furthermore, the rails and/or channels 2334can be arranged at an angle relative to the staple deck 2302 of thestaple cartridge 2330. In various embodiments, the rails and/or channels2334 can be arranged at an angle such that the cam 2322 and the distalcutting blade 2324 move distally as the blade 2324 deploys from thedistal cavity. In various circumstances, arranging the rails at such anangle can reduce the amount of force required to actuate the firingmember 2326 by aligning a component of the movement of the cam 2322 andthe blade 2324 along a longitudinal axis along which the firing member2326 moves. Arranging the rails at such an angle can also reduce thelikelihood of binding between the cam 2322 and the firing member 2326and/or between the cam 2322 and the rails and/or channels 2324 in thedistal cavity 2332.

In various embodiments, the firing member 2326 can be moved distallyfrom an unactuated position to an actuated position by the cutting blade2312 and/or a staple driver 2340. In various embodiments, the firingmember 2326 can be integral with the tissue-cutting blade 2312 and/orthe staple driver 2340 such that the firing member 2326 travels throughthe staple cartridge 2330 and along a longitudinal axis of the staplecartridge 2330 with the tissue cutting blade 2312 and/or the stapledriver 2340. In various other embodiments, the firing member 2326 can beseparate from the tissue-cutting blade 2312 and/or the staple driver2340. In such embodiments, the tissue-cutting blade 2312 and/or thestaple driver 2340 can push the firing member 2326 through the staplecartridge 2330. Alternatively, in such embodiments in which the firingmember 2326 is separate from the tissue-cutting blade 2312 and/or thestaple driver 2340, the firing member 2326 can be positioned at a distalend of the staple cartridge 2330 in an unactuated position, asillustrated in FIG. 82. The cutting blade 2312 and/or the staple driver2340 can travel through the staple cartridge 2330 and then push thefiring member 2326 into the actuated position illustrated in FIG. 83 asthe cutting blade 2312 and/or the staple driver 2340 reach the distalend of the staple cartridge 2330. In all of these embodiments, motion ofthe tissue-cutting blade 2312 and/or the staple driver 2340 in adirection along a longitudinal axis of the staple cartridge 2330 cancause the distal cutting blade 2324 to deploy in a direction differentfrom the tissue-cutting blade and/or the staple driver 2340.

In various embodiments, the distal cutting blade 2324 is not deployed tosever the distal portion 2316 of the layer 2306 until the firing strokeof the tissue cutting blade 2312 and/or the staple driver 2340 have beencompleted or are almost completed. In such embodiments, the distalportion 2316 of the layer 2306 can remain attached to the staplecartridge 2330, thereby stabilizing the layer 2306 relative to thestaple cartridge 2330, until most or all of the staples have been firedby the staple driver 2340 and/or until patient tissue and the layer 2306have been severed by the tissue cutting blade 2312. In various otherembodiments, the distal cutting blade 2324 can be deployed to sever thedistal portion 2316 of the layer 2306 before the tissue cutting blade2312 and/or the staple driver 2340 have begun their firing stroke. Forexample, the firing member 2326 can be moved from the unactuatedposition illustrated in FIG. 82 to the actuated position illustrated inFIG. 83 by a first actuation of a firing trigger of a surgical stapler.A subsequent actuation of the firing trigger can move the tissue cuttingblade 2312 and/or the staple driver 2340. As a result, the distalportion 2316 of the layer 2306 can be detached from the staple cartridge2330 before the tissue cutting blade 2312 severs patient tissue and/orbefore the staples capture the layer 2306 and patient tissue. As anotherexample, the firing member 2326 can be actuated by a first trigger ofthe surgical instrument and the tissue-cutting blade 2312 and/or thestaple driver 2340 can be actuated by a second trigger.

As described above, the nose 2308 of the staple cartridge assembly 2300can include a panel 2310 that extends proximally from the nose 2308 andthat at least partially covers the distal portion 2316 of the layer2306. The panel 2310 can include an inward-facing surface 2309 that canface the distal portion 2316 of the layer 2306. In certain embodiments,the inward-facing surface 2309 of the panel 2310 can support the distalportion 2316 of the layer 2306 as the distal cutting blade 2324 seversthe distal portion 2316. In various circumstances, when the distalcutting blade 2324 is deployed, the distal cutting blade 2324 caneventually make contact with the inward-facing surface 2309, therebycompletely severing the distal portion 2316 of the layer 2306 from theremainder of the layer 2306.

The panel 2310 can also protect patient tissue from the distal cuttingblade 2324. In various circumstances, unaffected patient tissue that isnot severed by the tissue cutting blade 2312 and/or stapled by staplesfrom the staple cartridge 2330 can pass over an outward-facing surface2311 of the panel 2310. In such circumstances, the panel 2310 can shieldthe unaffected tissue from the distal cutting blade 2324. For example,as illustrated in FIG. 83, the panel 2310 can be positioned between thedistal cutting blade 2324 extending out of the distal cavity 2332 andpatient tissue proximate to the outward-facing surface 2311 of the panel2310, such that the patient tissue is not exposed to the distal cuttingblade 2324.

Referring now to FIGS. 77-79, a staple cartridge 20000 can comprise acartridge body 20010 and a tissue thickness compensator 20020 releasablyattached thereto. The staple cartridge 20000 can comprise any suitablearrangement of staples, staple cavities, and/or staple drivers which arefired by a sled, or firing member, passing distally through the staplecartridge 20000 to capture at least a portion of the tissue thicknesscompensator 20020 and at least a portion of the patient tissue withinthe staples, as described elsewhere herein. Such discussion of thestaples, staple cavities, and staple drivers is not repeated here forthe sake of brevity to the reader. Referring primarily now to FIGS. 77and 77A, the staple cartridge 20000 can include a sled 20060 which isadvanced distally by a firing member 20050. At a certain point duringthe distal progression of the firing member 20050 and the sled 20060,the sled 20060, for example, can be configured to release the tissuethickness compensator 20020 from the cartridge body 20010, asillustrated in FIGS. 78 and 79. For instance, the distal end 20022 ofthe tissue thickness compensator 20020 can be releasably retained to thedistal end of the cartridge body 20010 by a flexible clamp 20013 and aretention pin 20072 wherein the sled 20060 can defeat, or withdraw, theretention pin 20072. The flexible clamp 20013 can be configured tosecurely hold the tissue thickness compensator 20020 against the deck20015 of the cartridge body 20010. In such circumstances, the flexibleclamp 20013 can provide a sufficient clamping force to the tissuethickness compensator 20020 in order to hold the tissue thicknesscompensator 20020 in place. The retention pin 20072 may also securelyhold the tissue thickness compensator 20020 to the cartridge body 20010.For instance, referring to FIGS. 77 and 77A, the distal end 20022 of thetissue thickness compensator 20020 can comprise an aperture 20023defined therein which can be configured to receive the retention pin20072 and, owing to the interaction between the retention pin 20072 andthe sidewalls of the aperture 20023, the retention pin 20072 can preventthe tissue thickness compensator 20020 from sliding out between theclamp 20013 and the cartridge deck 20015. Moreover, the retention pin20072 and the clamp 20013 can co-operatively confine the movement of thetissue thickness compensator 20020 and, in various circumstances, thetop of the retention pin 20072 can abut or can be positioned closelyadjacent to the clamp 20013.

In use, further to the above, the retention pin 20072 can be lowered bythe sled 20060, as illustrated in FIGS. 78 and 79. More specifically,the retention pin 20072 can extend from a cam 20070 wherein the cam20070 can rest or sit upon a resilient member, or spring, 20012extending from a pan 20011 attached to the cartridge body 20010 and,when the sled 20060 engages the cam 20070, the sled 20060 can push thecam 20070 and the retention pin 20072 downwardly thereby compressing thespring 20012. The cartridge body 20010 can include guides 20018 definedtherein which confine the movement of the cam 20070 along asubstantially vertical path, i.e., a path perpendicular to cartridgedeck 20015. In various embodiments, the sled 20060 can include a camactuator 20062 which extends distally with respect to the staple driverlift surfaces 20063. Once the pin 20072 has been sufficiently lowered,the tissue thickness compensator 20020 can slide relative to cartridgedeck 20015 and slip out of the clamp 20013. In various circumstances,the pin 20072 can be lowered a sufficient amount while still at leastpartially protruding from the cartridge deck 20015. In othercircumstances, the pin 20072 can be lowered beneath the cartridge deck20015. In either event, the cam actuator 20062 and staple driver liftsurfaces 20063 of the sled 20060 can be configured such that theretention pin 20072 is sufficiently lowered at the same time that thelast, or distal-most, staple is fired by the sled 20060. In othercircumstances, the cam actuator 20062 and staple driver lift surfaces20063 of the sled 20060 can be configured such that the retention pin20072 is sufficiently lowered before the last, or distal-most, staple isfired by the sled 20060. In yet other circumstances, the cam actuator20062 and staple driver lift surfaces 20063 of the sled 20060 can beconfigured such that the retention pin 20072 is sufficiently loweredafter the last, or distal-most, staple is fired by the sled 20060.Although cam 20070 is described herein as having one retention pin20072, a plurality of retention pins 20072 can extend from the cam 20070which can each be configured to releasably retain the tissue thicknesscompensator 20020 to the cartridge body 20010. Accordingly, the tissuethickness compensator 20020 can include a suitable number of apertures20023 configured to receive the retention pins 20072.

Referring now to FIGS. 80 and 81, a cartridge 21000, for example, cancomprise a cartridge body 21010, a tissue thickness compensator 21020releasably secured to the cartridge body 21010, and a sled 21060 whichcan be configured to release the tissue thickness compensator 21020 fromthe cartridge body 21010. Similar to the above, the sled 21060 cancomprise staple driver lift surfaces 21063 which are configured to liftstaple drivers, and staples supported thereon, toward an anvilpositioned opposite the tissue thickness compensator 21020. Also similarto the above, the sled 21060 can further comprise a cam actuator 21062which can be configured to deactivate a clamp 21013 holding a distal end21022 of the tissue thickness compensator 21020 to the deck surface21015 of the cartridge body 21010. More specifically, the clamp 21013can include a cam 21072 extending downwardly into the cartridge body21010 wherein the cam 21072 can be engaged by the cam actuator 21062 asthe sled 21060 is advanced distally through the staple cartridge 21000.When the cam actuator 21062 engages the cam 21072, the cam actuator21062 can lift the cam 21072 upwardly and flex the clamp 21013 away fromthe distal end 21022 of the tissue thickness compensator 21020, asillustrated in FIG. 81. At such point, the cartridge body 21010 can bemoved away from the tissue thickness compensator 21020. Stated anotherway, by the time that the tissue thickness compensator 21020 is releasedfrom the cartridge body 21010, the tissue thickness compensator 21020will have been implanted to the patient tissue by one or more stapleswherein, after the tissue thickness compensator 21020 has been released,the cartridge body 21010 can be moved away from the implanted tissuethickness compensator 21020 and removed from the surgical site.

Further to the above, the cam actuator 21062 and staple driver liftsurfaces 21063 of the sled 21060 can be configured such that the cam20072 is sufficiently raised to sufficiently reduce the clamping forceapplied by the clamp 21013 at the same time that the last, ordistal-most, staple is fired by the sled 20060. In other circumstances,the cam actuator 21062 and staple driver lift surfaces 21063 of the sled21060 can be configured such that the cam 21072 is sufficiently raisedto sufficiently reduce the clamping force applied by the clamp 21013before the last, or distal-most, staple is fired by the sled 21060. Inyet other circumstances, the cam actuator 21062 and staple driver liftsurfaces 21063 of the sled 21060 can be configured such that the cam20072 is sufficiently raised to sufficiently reduce the clamping forceapplied by the clamp 21013 after the last, or distal-most, staple isfired by the sled 21060. Although the clamp 21013 is described herein ashaving one cam 21072 extending therefrom, a plurality of cams 21072 canextend from the clamp 21013 which can each be configured to lift theclamp 21013 and release the tissue thickness compensator 20020 from thecartridge body 20010.

Further to the above, a sled, or firing member, passing through a staplecartridge can release a tissue thickness compensator from a cartridgebody at the end, or near the end, of the distal movement of the sledand/or the end of the firing stroke of the firing member. Stated anotherway, the tissue thickness compensator can be released from the cartridgebody at the same time, or nearly the same time, that all of the stapleshave been fired from the staple cartridge. In various other embodiments,the tissue thickness compensator can be released from the cartridge bodyat the same time, or before, the first, or proximal-most, staples havebeen fired from the staple cartridge. One such exemplary embodiment isdepicted in FIGS. 90-92 which illustrate a staple cartridge 22000.Similar to the above, the staple cartridge 22000 can comprise acartridge body 22010 and a tissue thickness compensator 22020 releasablysecured thereto. Although the staple cartridge 22000 can further includea staple-firing sled as described above, the sled may not release thetissue thickness compensator 22020; rather, the staple cartridge 22000may further comprise an actuator 22011 which can be advanced distally bythe firing member at the beginning of the firing stroke thereof. Variousother embodiments are disclosed herein which disclose means foradvancing an actuator distally and are not repeated with regard to thisembodiment for sake of brevity to the reader. In any event, the actuator22011 can include a cam support 22012 extending therefrom which can beconfigured to support a cam 22070 when the actuator 22011 is in itsunactuated position, as illustrated in FIG. 90. Moreover, the staplecartridge 22000 can further comprise a biasing member, or spring, 22074which can be configured to hold or bias the cam 22070 against the camsupport 22012 while, again, the actuator 22011 is in its unactuatedposition illustrated in FIG. 90. In such a position of the cam 22070, aretention pin 22072 extending from the cam 22070 can be engaged with andextend through an aperture 22023 defined in a distal end 22022 of thetissue thickness compensator 22020 such that, similar to the above, theretention pin 22072, and/or the retention pin 22072 in concert with aclamp 22013 extending from the cartridge body 22010, can hold the tissuethickness compensator 22020 in position.

When the actuator 22011 is advanced distally by the firing member,referring now to FIG. 91, the cam support 22012 can be advanced distallysuch that the cam support 22012 may no longer support the cam 22070. Insuch circumstances, the spring 22074 may bias the cam 22070 downwardlysuch that the retention pin 22072 is biased out of engagement, or atleast partially out of engagement, with the tissue thickness compensator22020. In at least one circumstance, the spring 22074 can bias the cam22070 downwardly such that the retention pin 22072 is positioned belowthe deck 22015 of the cartridge 22010. In any event, the distaladvancement of the actuator 22011 can release the tissue thicknesscompensator 22020 from the cartridge body 22010. Stated another way,once the retention pin 22072 has been lowered, the clamp 22013 may stillprovide a holding force to the tissue thickness compensator 22020 suchthat the tissue thickness compensator 22020 remains pinned against thestaple deck 22015; however, the tissue thickness compensator 22020 canbe slid out from underneath the clamp 22013 upon the application of asufficient relative force between the tissue thickness compensator 22020and the cartridge body 22010. Further to the above, the release of thetissue thickness compensator 22020 from the cartridge body 22010 canoccur before, contemporaneous with, and/or immediately after theproximal-most staples are fired from the staple cartridge 22000. In suchcircumstances, the early release of the tissue thickness compensator22020 may permit the tissue thickness compensator 22020 to be releasedfrom the cartridge body 22010 even though the staple cartridge 22000 hasonly been partially fired, for example.

Referring now to FIGS. 84-87, an end effector assembly 5000 can includea first jaw, illustrated elsewhere, and a second jaw 5002. In variousembodiments, the second jaw 5002 can include a cartridge assembly thatincludes a fastener cartridge body 5050 and a tissue thicknesscompensator 5058 releasably secured to the fastener cartridge body 5050.Referring primarily to FIG. 84, the fastener cartridge body 5050 canhave a cartridge deck 5052 and fastener cavities 5054 defined in thecartridge deck 5052. Further, the second jaw 5002 can include fasteners,such as surgical staples, for example, which can be removably positionedin the fastener cavities 5054. For example, a fastener can be ejectablypositioned in each fastener cavity 5054 of the cartridge body 5050. Incertain embodiments, the cartridge body 5050 can include a slot 5056,which can extend from a proximal portion 5004 of the second jaw 5002toward a distal portion 5006 of the second jaw 5002. In variousembodiments, a firing assembly 5030 can translate along the slot 5056 ofthe cartridge body 5050. For example, the firing assembly 5030 cantranslate within the slot 5056 during a firing stroke, and can eject thefasteners from the fastener cavities 5054 during the firing stroke.

Referring primarily to FIGS. 84, 86 and 87, the firing assembly 5030 caninclude a firing bar (FIG. 84), a cutting edge 5036, a crossbar 5038,and a foot 5044 (FIGS. 86 and 87). The cutting edge 5036 can cut tissueand/or cut the tissue thickness compensator 5058 as the firing assembly5030 is fired through the second jaw 5002 during a firing stroke. Thecrossbar 5038 can hold the first jaw relative to the cartridge body5050, and the foot 5044 can hold the firing assembly 5030 relative tothe cartridge body 5050, for example. In various embodiments, thecrossbar 5038 and the foot 5044 can hold the cutting element 5036perpendicular to the deck 5052 of the fastener cartridge 5050, forexample. Referring primarily to FIGS. 29A and 29B, the firing assembly5030 can engage a sled 5034 in the cartridge body 5050 during the firingstroke. The firing assembly 5030 can push the sled 5034 distally duringthe firing stroke to eject fasteners from the fastener cavities 5054,for example.

Referring primarily to FIG. 84, the tissue thickness compensator 5058can be releasably secured to the cartridge body 5050 by at least oneconnector 5080 a, 5080 b. In certain embodiments, multiple connectors5080 a, 5080 b can secure the tissue thickness compensator 5058 to thecartridge body 5050. For example, a proximal connector 5080 a can securethe tissue thickness compensator 5058 to the cartridge body 5050 at theproximal portion 5004 of the second jaw 5002, and a distal connector5080 b can secure the tissue thickness compensator 5058 to the cartridgebody 5050 at the distal portion 5006 of the second jaw 5002. In certainembodiments, additional connectors can secure the tissue thicknesscompensator 5058 to the cartridge body 5050. In such embodiments, theadditional connectors can be spaced along at least a portion of thelength of the cartridge body 5050, and can be positioned between theproximal connector 5080 a and the distal connector 5080 b, for example.

Still referring primarily to FIG. 84, the connectors 5080 a, 5080 b canhold the tissue thickness compensator 5058 relative to the cartridgebody 5050. The tissue thickness compensator 5058 can be released fromthe cartridge body 5050 when the connectors 5080 a, 5080 b are broken,cut, dislodged or otherwise overcome. In certain embodiments, the firingassembly 5030 can overcome the connectors 5080 a, 5080 b as the firingassembly 5030 translates along the slot 5056 in the fastener cartridge5050 during a firing stroke. During such a firing stroke, the firingassembly 5030 can cut tissue clamped between the first jaw and thesecond jaw 5002, and can also move the fasteners from the fastenercavities 5054 into the clamped tissue. In various embodiments, thefiring assembly 5030 can push the sled 5034 (FIGS. 86 and 87) distallyduring the firing stroke. The sled 5034 can have a camming surface orramp 5042, which can engage drivers in the fastener cavities 5054. Whenthe ramp 5042 engages a driver, the ramp 5042 can push the driver towardthe deck 5052 to eject the fastener from the fastener cavity 5054.Further, the firing assembly 5030 can cut the tissue thicknesscompensator 5058 and the connectors 5080 a, 5080 b during the firingstroke.

Referring primarily to FIG. 84, the cutting edge 5036 of the firingassembly 5030 can cut the proximal connector 5080 a at or near thebeginning of the firing stroke, for example, and can cut the distalconnector 5080 b at or near the end of the firing stroke, for example.In certain embodiments, the sled 5034 (FIGS. 86 and 87) can eject thefasteners from the fastener cavities 5054 after the cutting edge 5036cuts the proximal connector 5080 a and before the cutting edge 5036 cutsthe distal connector 5080 b. In such embodiments, if the firing assembly5030 does not complete the firing stroke, the cutting edge 5036 of thefiring assembly 5030 may stop before reaching the distal connector 5080b, and the tissue thickness compensator 5058 may remain secured to thecartridge body 5050 at the distal portion 5006 of the second jaw 5002.In certain embodiments, the tissue thickness compensator 5058 can remainsecured to the cartridge body 5050 until the operator cuts or otherwiseovercomes the distal connector 5080 b. For example, the operator mayintroduce an additional surgical instrument and/or step in the surgicalprocedure to overcome the distal connector 5080 b.

Referring still to FIGS. 84-87, in various embodiments, the second jaw5002 can overcome the connectors 5080 a, 5080 b at or near the beginningof the firing stroke. In other words, an element of the second jaw 5002can overcome the proximal connector 5080 a, the distal connector 5080 b,and any additional connectors therebetween at or near the beginning ofthe firing stroke. For example, the second jaw 5002 and/or the cartridgeassembly can include an actuator 5010, which can overcome the distalconnector 5080 b before the fasteners are ejected from the fastenercavities. The actuator 5010 can overcome the distal connector 5080 b andthe tissue thickness compensator 5358 can be released from the cartridgebody 5050 even when the firing stroke terminates prematurely, i.e.,before the firing assembly 5030 reaches the distal portion 5006 of thesecond jaw 5002, for example. In various embodiments, the actuator 5010can include a bottom side 5016 (FIGS. 85A-85C) and sidewalls 5018 (FIGS.84 and 85D). The sidewalls 5018 can extend from the bottom side 5016 andaround at least a portion of the cartridge body 5050. The bottom side5016 and/or the sidewalls 5018 can extend past or around the fastenerspositioned in the fastener cavities 5054. Further, the actuator 5010 canbe moveably held relative to the cartridge body 5050. For example, theactuator 5010 can move from a pre-actuated position (FIG. 85A) to anactuated position (FIGS. 85B and 85D). In certain embodiments, thesidewalls 5018 of the actuator 5010 can engage slits in the cartridgebody 5050, such that the actuator 5010 moves in the slits to sliderelative to the cartridge body 5050. When the actuator 5010 movesrelative to the cartridge body 5050, the actuator 5010 can sliderelative to the fasteners positioned in fastener cavities 5054 of thecartridge body 5050. For example, the actuator 5010 can slide pastand/or around the fasteners positioned in the fastener cavities 5054.

Referring primarily to FIGS. 85A-85C, the actuator 5010 can include aslot 5012, which can extend from the proximal portion 5004 toward thedistal portion 5006 of the second jaw 5002. The slot 5012 in theactuator 5010 can correspond to and/or be aligned with the slot 5056(FIG. 84) in the cartridge body 5050, for example. Further, the firingassembly 5030 can translate along and/or within the slot 5012 in theactuator 5010 as the firing assembly 5030 translates along and/or withinthe slot 5056 in the cartridge body 5050 during the firing stroke. Invarious embodiments, the firing assembly 5030 can engage the actuator5010 to move the actuator 5010 distally when the firing assembly 5030 isat or near the beginning of the firing stroke. In such embodiments, thefiring assembly 5030 can actuate the actuator 5010 at the proximalportion 5004 of the second jaw 5002. When the actuator 5010 is actuatedand moves distally, a distal end of the actuator 5010 can cut orotherwise overcome the distal connector 5080 b, for example. In otherwords, proximal actuation of the actuator 5010 can effectuate distalrelease of the tissue thickness compensator 5058 from the cartridge body5050. In various embodiments, the actuator 5010 can merely shiftdistally to overcome the distal connector 5080 b. In at least oneembodiment, the actuator 5010 can shift approximately 1 mm, for example,before overcoming the distal connector 5080 b. In certain embodiments,the actuator 5010 can shift approximately 0.5 mm to approximately 5 mm,for example, before overcoming the distal connector 5080 b.

Referring primarily to FIGS. 85A and 85B, the actuator 5010 can movefrom the pre-actuated position (FIG. 85A) to the actuated position (FIG.85B) when the firing assembly 5030 moves between an unfired position anda partially fired position during part of the firing stroke. In variousembodiments, the actuator 5010 can include a release stop, such asdetent tabs 5022, for example. The progression of the firing elementrelative to the actuator 5010 can be paused by the detent tabs 5022. Inother words, the detent tabs 5022 can temporarily halt the progressionof the firing assembly 5030 relative to the actuator 5010. For example,while the actuator 5010 moves from the pre-actuated position toward theactuated position, the detent tabs 5022 can engage the sled 5034 and/orthe firing assembly 5030 to hold the firing assembly 5030 relative tothe actuator 5010, such that the actuator 5010 moves therewith. Forexample, referring primarily to FIGS. 86 and 87, the bottom side 5016 ofthe actuator 5010 can include a detent tab 5022, and the sled 5034 caninclude a recess or groove 5040. In various embodiments, the groove 5040can receive the tab 5022 when the sled 5034 is positioned in theproximal portion 5004 of the second jaw 5002. For example, the groove5040 can be aligned with the tab 5022 when the firing assembly 5030moves from an unfired position to a fired position, and thus, when theactuator is pushed from a pre-actuated position (FIG. 85A) to anactuated positioned (FIG. 85B). In various embodiments, at least one tab5022 can be positioned on either side of the slot 5012 (FIGS. 85A-85C)in the actuator 5010, and each tab 5022 can engage the sled 5034.

Referring primarily to FIG. 85A, the sled 5034 can engage the detenttabs 5022 as the firing assembly 5030 and sled 5034 translate along theslot 5056 (FIG. 84) during the firing stroke. For example, the detenttabs 5022 can engage the sled 5034 at or near the beginning of thefiring stroke. In certain embodiments, the detent tabs 5022 can be nearthe proximal end of the actuator 5010, and the sled 4034 can engage thedetent tabs 5022 upon the initiation of the firing stroke. When thefiring bar 5032 is moved distally and the detent tabs 5022 are engagedwith the recesses 5040 in the sled 5034 (FIGS. 86 and 87), the actuator5010 can be driven and/or shifted distally. In certain embodiments,referring primarily to FIG. 85B, the actuator 5010 can move distallyuntil it reaches a hard stop 5060 defined in the cartridge body 5050,for example. The hard stop 5060 can be at the distal portion 5006 of thesecond jaw 5002, and can prevent further distal movement of the actuator5010, for example. In various embodiments, the actuator 5010 can abutthe hard stop 5060 before the firing assembly 5030 ejects the fastenersfrom the fastener cavities 5054 of the cartridge body 5050 (FIG. 84). Insome embodiments, the actuator 5010 can abut the hard stop 5060 as thefiring assembly 5030 ejects at least one fastener from a fastener cavity5054 and/or after the firing assembly 5030 has ejected at least onefastener from a fastener cavity 5054.

Referring primarily to FIG. 85D, when the actuator 5010 is pusheddistally by the sled 5034 and/or the firing assembly 5030, the actuator5010 can cut or otherwise overcome the distal connector 5080 b torelease the tissue thickness compensator 5058 from the cartridge body5050 at the distal portion 5006 of the second jaw 5002. In certainembodiments, the actuator 5010 can include a notch 5024 for receivingand holding the distal connector 5080 b. The notch 5024 can hold thedistal connector 5080 b as the actuator 5010 shifts distally toward thehard stop 5060. Further, the actuator 5010 can include a cutting edge5020, for example, along the notch 5024. In certain embodiments, whenthe actuator 5010 moves toward the hard stop 5060, the distal connector5080 b can be pushed between the hard stop 5060 and the cutting edge5020 of the actuator 5010. In various embodiments, the cutting edge 5020can cut the distal connector 5080 b when the cutting edge 5020 is pushedinto and/or toward the hard stop 5060. In such embodiments, the distalconnector 5080 b can be cut by the cutting edge 5020 of the actuator5010 at or near the beginning of the firing stroke and before thefasteners are fired from the fastener cavities 5054 (FIG. 84). In someembodiments, the cutting edge 5020 can cut the distal connector 5080 bas the firing assembly 5030 ejects at least one fastener from a fastenercavity 5054 and/or after the firing assembly 5030 has ejected at leastone fastener from a fastener cavity 5054. In various embodiments, theactuator 5010 can overcome the distal connector 5080 b without cuttingit. For example, the actuator 5010 can dislodge or stretch the distalconnector 5080 b out of position such that the distal connector 5080 bno longer holds the tissue thickness compensator 5058 relative to thecartridge body 5050.

In various embodiments, the proximal connector 5080 a can be cut by aproximal cutting edge on the actuator 5010. Similarly, additionalconnectors along the length of the cartridge body 5050 can be cut orotherwise overcome by the actuator 5010 at or near the beginning of thefiring stroke. Additionally or alternatively, the cutting edge 5036 ofthe firing assembly 5030 can cut or otherwise overcome the proximalconnector 5080 a and/or additional connectors. For example, the cuttingedge 5036 of the firing assembly 5030 can cut the proximal connector5080 a and the cutting edge 5020 of the actuator 5010 can cut the distalconnector 5080 b before the fasteners are ejected from the fastenercavities 5054 of the cartridge body 5050 (FIG. 84).

Referring primarily to FIG. 87, the sled 5034 and/or the firing assembly5030 can be configured to overcome the detent tabs 5022 of the actuator5010. When the sled 5034 and/or the firing assembly 5030 overcome thedetent tabs 5022, the firing assembly 5030 and the sled 5034 can moverelative to the actuator 5010. For example, the firing assembly 5030 canpush the sled 5034 distally to move the actuator 5010 distally untilfurther distal movement of the actuator is prevented by the hard stop5060 (FIGS. 85A, 85C, and 85D). Referring still to FIG. 87, when theactuator 5010 is blocked from further distal movement, the firingassembly 5030 can push the sled 5034 with sufficient force to deform,deflect, and/or dislodge the detent tabs 5022 from the recesses 5040 inthe sled 5034. For example, the tabs 5022 can each comprise a cantileverwhich can flex downwardly out of engagement with the groove 5040 after asufficient longitudinal force has been applied to the sled 5034. Whenthe firing assembly 5030 pushes the sled 5034 out of engagement with thedetent tabs 5022, the firing assembly 5030 and sled 5034 can moverelative to the actuator 5010. In various embodiments, the detent tabs5022 can be sufficiently rigid to withstand the force of the firingassembly 5030 as the actuator 5010 shifts distally toward the hard stop5060, and can be sufficiently flexible to deflect when the actuator 5010reaches the hard stop 5060 without requiring excessive force by a motorand/or operator. In various circumstances, the detent tabs 5022 can beconfigured to permit the firing bar 5032 to pass through the cartridgebody 5050 after the force applied to detent tabs 5022 has exceeded apredetermined force.

Referring now to FIGS. 29A and 29B, an end effector assembly 5100 caninclude a first jaw, illustrated elsewhere, and a second jaw 5102. Invarious embodiments, the second jaw 5102 and/or a fastener cartridgeassembly positionable therein can include an actuator 5110. The actuator5110 can slide or shift relative to a fastener cartridge body, such asthe fastener cartridge body 5050 (FIG. 84), for example, of the fastenercartridge assembly. Further, in certain embodiments, the actuator 5110can include a bottom wall 5116 and sidewalls 5118, which can bepositioned at least partially around the cartridge body 5050. The bottomwall 5116 and/or the sidewalls 5118 can extend past or around thefasteners positioned in the fastener cavities 5054 (FIG. 84) when theactuator is held relative to the cartridge body 5050. In variousembodiments, the actuator 5110 can include a slot 5112 extending alongat least a portion of the bottom wall 5116. Further, the sidewalls 5118can include lips 5122 and/or lips 5124, which can slidably engage thecartridge body 5050. For example, the lips 5122 can extend around thecartridge body 5050 and into slits in the deck 5052 (FIG. 84) of thecartridge body 5050. Further, the lips 5124 can extend into slits alongthe side of the cartridge body 5050, for example. In variousembodiments, the lips 5122, 5124 can slide within the slits as theactuator 5110 moves relative to the cartridge body 5050. In suchembodiments, the lips can constrain and/or define the relative movementbetween the actuator 5110 and the cartridge body 5050, for example. Whenthe actuator 5110 moves relative to the cartridge body 5050, theactuator 5110 can slide relative to the fasteners positioned in thefastener cavities 5054 of the cartridge body 5050. For example, theactuator 5110 can slide past or around the fasteners in the fastenercavities 5054.

Referring still to FIGS. 29A and 29B, the actuator 5110 can include arelease stop, such as detent 5114, for example, at the proximal portion5104 of the second jaw 5102, for example. Referring primarily to FIG.29A, the detent 5114 can include a detent arm 5120 which can operablyhold a sled 5134 of the cartridge body 5050 (FIG. 84). For example, thesled 5134 can include a groove 5144 and the detent arm 5120 can engagethe groove 5144 to retain the sled 5134 relative to the actuator 5110.In various embodiments, the detent 5114 can have multiple detent arms5120, which can be retained in grooves 5144 in the sled 5134. The detentarms 5120 can extend from opposite sides of the actuator 5110, forexample, and the sled 5134 can be positioned intermediate the detentarms 5120, for example. In certain embodiments, the firing assembly 5030can push against the sled 5134 and can shift the actuator 5110 distallywhile the detent arms 5120 are held in the grooves 5144 of the sled 5134(FIG. 29A). The detent arms 5120 can be sufficiently rigid to hold thesled 5134 relative to the actuator 5110 as the actuator 5110 is pusheddistally by the firing assembly 5030. Thereafter, the actuator 5110 canabut a hard stop, such as hard stop 5060 (FIGS. 84-85B and 85D), forexample, which can prevent further distal movement of the actuator 5110.

Referring primarily to FIG. 29B, when the actuator 5010 abuts the hardstop 5060 (FIGS. 84-85B and 85D), the firing assembly 5030 can push thesled 5134 through the detent 5114. In other words, the firing assembly5030 can force the sled 5134 to overcome the detent arms 5120. In suchembodiments, the detent arms 5120 can be sufficiently flexible to flexout of engagement with the grooves 5144 of the sled 5134 and permitpassage of the firing assembly 5030 between the detent arms 5120 andalong the slot 5112 in the actuator 5110. Similar to the actuator 5010,the actuator 5110 can include an edge that can cut or otherwise overcomea distal connector, similar to distal connector 5080 b (FIGS. 84 and85D), for example, when the actuator 5110 is shifted distally by thefiring assembly 5030. Thereafter, the firing assembly 5030 and the sled5134 can translate along the slot 5112, and can eject fasteners from thefastener cavities 5054 in the cartridge body, for example. In variousembodiments, the actuator 5110 can overcome the distal connector and/oradditional connector(s) before a fastener is fired from the fastenercartridge 5050. In certain embodiments, the actuator 5110 can overcomethe distal connector and/or additional connector(s) as at least onefastener is fired from a fastener cavity and/or after at least onefastener has been fired from a fastener cavity.

Referring now to FIGS. 87A and 87B, an end effector assembly 5200 caninclude a first jaw, illustrated elsewhere, and a second jaw 5202. Invarious embodiments, the second jaw 5202 and/or a fastener cartridgeassembly can include an actuator 5210 that can slide relative to afastener cartridge body, such as the fastener cartridge body 5050 (FIG.84), for example. Further, in certain embodiments, the actuator 5210 caninclude a bottom wall 5216 and sidewalls. The sidewalls can bepositioned at least partially around the cartridge body 5050, forexample. The actuator 5210 can include a slot 5212 extending along atleast a portion of the bottom wall 5216. Further, the actuator 5210 canbe moveably held relative to the cartridge body 5050. When the actuator5210 moves relative to the cartridge body 5050, the actuator 5210 canmove relative to the fasteners positioned in the fastener cavities 5054of the cartridge body 5050. For example, the actuator 5210 can slidepast or around the fasteners positioned in the fastener cavities 5054.

In various embodiments, the firing assembly 5030 can translate alongand/or within the slot 5212 during a firing stroke. Similar to theactuators 5010, 5110, the actuator 5210 can include a release stop 5214.In various embodiments, the release stop 5214 can include a frangibleportion 5220, which can be a bridge across the slot 5212, for example.Referring primarily to FIG. 87A, the firing assembly 5030 can abut therelease stop 5214 to push the actuator 5210 distally. Thereafter, theactuator 5210 can abut a hard stop, such as hard stop 5060 (FIGS. 84-85Band 85D), which can prevent further distal movement of the actuator5210. Referring primarily to FIG. 87B, upon reaching the hard stop 5060,the firing assembly 5030 can break the frangible portion 5220 of therelease stop 5214 to continue moving distally along the slot 5212 duringthe firing stroke. The frangible portion 5220 can be sufficiently rigidto withstand the force of the firing assembly 5030 as the actuator 5210shifts distally toward the hard stop 5060 (FIG. 85D), and can besufficiently frangible to break when the actuator 5210 reaches the hardstop 5060 without requiring excessive force by a motor and/or operator.In various embodiments, the actuator 5210 can overcome the distalconnector 5080 b and/or additional connector(s) before a fastener isfired from the fastener cartridge 5050. In certain embodiments, theactuator 5210 can overcome the distal connector and/or additionalconnector(s) as at least one fastener is fired from a fastener cavityand/or after at least one fastener has been fired from a fastenercavity.

Referring now to FIGS. 88 and 89, an end effector assembly 5300 caninclude a first jaw, illustrated elsewhere, and a second jaw 5302. Invarious embodiments, the second jaw 5302 can include a cartridge body5350 and a tissue thickness compensator 5358 releasably secured to thecartridge body 5350. Similar to the second jaw 5002, the second jaw 5302can include fasteners, such as surgical staples, for example, which canbe removably positioned in fastener cavities in the cartridge body 5350.For example, a fastener can be ejectably positioned in each fastenercavity. In certain embodiments, the cartridge body 5350 can include aslot 5356 (FIG. 88), which can extend from a proximal portion 5304toward a distal portion 5306 of the second jaw 5302. In variousembodiments, the firing assembly 5030 can translate along the slot 5356of the cartridge body 5350. The firing assembly 5030 can translatewithin the slot of the fastener cartridge 5350 during a firing stroke,and can eject the fasteners from the fastener cavities during the firingstroke, for example. The firing assembly 5030 can engage a sled 5334(FIG. 89) in the cartridge body 5350 during the firing stroke, forexample, and can push the sled 5334 distally during the firing stroke,for example. Furthermore, during the firing stroke, the firing assembly5030 and/or an actuator 5310 can release the tissue thicknesscompensator 5358 from the cartridge body 5350.

Referring still to FIGS. 88 and 89, the tissue thickness compensator5358 can include a body 5360, a proximal mount 5362 extending from thebody 5360, and a distal mount 5364 extending from the body 5360.Referring primarily to FIG. 89, a pin 5366 can extend through theproximal mount 5362 into an opening 5356 a in the cartridge body 5350,such that the pin 5366 releasably holds the tissue thickness compensator5358 relative to the cartridge body 5350 at the proximal portion 5304 ofthe second jaw 5302, for example. The pin 5366 can be friction fitand/or snap-fit into the opening 5356 a, for example. In certainembodiments, the pin 5366 can be held in the opening 5456 a utilizingone or more adhesives, for example. In some embodiments, at least aportion of the cartridge body 5350 and/or pin 5366 can be welded, forexample. In various embodiments, the tissue thickness compensator 5358can include multiple proximal mounts 5362, which can be releasablysecured to the cartridge body 5350 on either side or both sides of theslot 5356 (FIG. 88) in the cartridge body 5350. In certain embodiments,the distal mount 5364 can be secured to the cartridge body 5350 at thedistal portion 5306 of the second jaw 5302, for example. The distalmount 5364 can be secured to the cartridge body 5350 via at least oneadhesive between the distal mount 5364 and the cartridge body 5350, forexample. Additionally or alternatively, the distal mount 5364 can besecured to the cartridge body 5350 by at least one pin and/or otherfastener, for example.

Referring primarily to FIG. 89, the actuator 5310 can loop around thedistal mount 5364 and can extend to the sled 5334 in the second jaw5302. In various embodiments, the actuator 5310 can comprise a cable orcord, which can extend through the cartridge body 5350 and/or through achannel 5346 defined in the second jaw 5302 and/or in the sled 5334, forexample. In various embodiments, distal movement of the sled 5334 canpull the actuator 5310 to break through the distal mount 5364 of thetissue thickness compensator 5358. For example, the actuator 5310 canhave a first end 5316 secured to the sled 5334, a second end 5318secured within the cartridge body 5350, and a loop 5320 between thefirst end 5316 and the second end 5318. The loop 5320 can loop aroundthe distal mount 5364, for example. In various embodiments, the loop5320 can wrap around the distal mount 5364 between the portion of thedistal mount 5364 that is secured to the cartridge body 5350 and thebody 5360 of the tissue thickness compensator 5358. In certainembodiments, the second end 5318 can be fixedly secured in the cartridgebody 5350, such that when the first end 5316 moves, the loop 5320tightens around the distal mount 5364. In various embodiments, thesecond jaw 5302 and/or the cartridge body 5350 can include buttons,pins, and/or castors, such as a first button 5312 and a second button5314, for example. The actuator 5310 can wrap around the first button5312 and the second button 5314, for example. The position of thebuttons 5312, 5314 and the orientation of the actuator 5310 around thebuttons 5312, 5314 can cause the loop 5320 of the actuator 5310 totighten around the distal mount 5364 when the sled 5334 and the firingassembly 5330 move distally during a firing stroke. Further, as the loop5320 tightens around the distal mount 5364, the loop 5320 can breakthrough the distal mount 5364 to release the body 5360 of the tissuethickness compensator 5358 from the cartridge body 5350 at the distalportion 5306 of the second jaw 5302. As such, in view of the above, thedistal mount 5364 can be disengaged during the beginning of the firingstroke.

In various embodiments, when the distal mount 5364 of the tissuethickness compensator 5358 is released from the cartridge body 5350, thepin 5366 securing the proximal mount 5362 of the tissue thicknesscompensator 5358 to the cartridge body 5350 can be released from theopening 5356 in the cartridge body 5350. For example, at or near thebeginning of a stroke, the pin 5366 can be released from the opening5356. The pin 5366 can be sheared and/or severed by the cutting edge5036 of the firing assembly 5030, for example, and/or can be pushedand/or driven out of the opening 5356 by an element of the firingassembly 5030. In such embodiments, the tissue thickness compensator5358 can be released from the cartridge body 5350 at or near thebeginning of the firing stroke when both the proximal mount 5362 and thedistal mount 5364 are released from the cartridge body 5350. In otherwords, the actuator 5310 can release the tissue thickness compensator5358 from the cartridge body 5350 prior to the firing assembly 5030and/or the sled 5334 ejecting the fasteners from the fastener cavitiesin the cartridge body 5350. In some embodiments, the firing assembly5030 and/or the sled 5334 can eject at least one fastener from afastener cavity before and/or while the actuator 5310 releases thetissue thickness compensator 5358 from the cartridge body 5350.

A fastener cartridge assembly can comprise a cartridge body comprising aplurality of fastener cavities and a slot. The fastener cartridgeassembly can further comprise a plurality of fasteners, wherein eachfastener is removably positioned in a fastener cavity. The fastenercartridge assembly can further comprise a firing element configured tomove along the slot, a tissue thickness compensator releasably securedto the cartridge body, and a mount, wherein the mount secures the tissuethickness compensator to the cartridge body, and wherein the mount ispositioned distal to a fastener of the plurality of fasteners. Thefastener cartridge assembly can further comprise a cable between thefiring element and the mount, wherein the cable is configured to breakthe mount when the firing element moves distally along the slot. Thetissue thickness compensator can be released from the cartridge bodywhen the cable breaks the mount. The cable can break the mount prior tothe removal of the fasteners from the fastener cavities. The fastenercartridge assembly can further comprise a channel, wherein the cableextends through the channel.

Referring now to FIGS. 93A-93D, an end effector assembly 5600 caninclude a first jaw, illustrated elsewhere, and a second jaw 5602. Invarious embodiments, the second jaw 5602 can include a fastenercartridge body 5650 and a tissue thickness compensator 5658 releasablysecured to the second jaw 5602 and/or to the fastener cartridge body5650. In certain embodiments, the fastener cartridge body 5650 and thetissue thickness compensator 5658 releasably secured thereto cancomprise a fastener cartridge assembly. Referring primarily to FIG. 93A,the cartridge body 5650 can have a cartridge deck 5652 and fastenercavities 5654 defined in the cartridge deck 5652. Further, the secondjaw 5602 can include fasteners, such as surgical staples, for example,which can be removably positioned in the fastener cavities 5654. Forexample, a single fastener can be ejectably positioned in each fastenercavity 5654 of the cartridge body 5650. Still referring primarily toFIG. 93A, the cartridge body 5650 can include a ridge 5648 extendingfrom the cartridge deck 5652. The ridge 5648 can extend around at leasta portion of a fastener cavity 5654, for example. In variousembodiments, when a fastener is positioned in a fastener cavity 5654,the tip of the fastener can protrude from the fastener cavity 5654. Insuch embodiments, the ridge 5648 positioned at least partially aroundthe fastener cavity 5654 can support and/or guide the tip of thefastener when the fastener is ejected from the fastener cavity 5654. Incertain embodiments, referring still to FIG. 93A, the cartridge body5650 can include a slot 5656, which can extend from a proximal portion5604 of the second jaw 5602 toward a distal portion 5606 of the secondjaw 5602. In various embodiments, a firing assembly 5630 can translatealong the slot 5656 of the cartridge body 5650. For example, the firingassembly 5630 can translate along the slot 5656 during a firing stroke,and can eject fasteners from the fastener cavities 5654 during thefiring stroke.

Referring still to FIGS. 93A-93D, the firing assembly 5630 can include afiring bar 5632, a cutting edge 5636, a crossbar 5638, and a foot 5644.The cutting edge 5636 can cut tissue and/or cut the tissue thicknesscompensator 5658 as the firing assembly 5630 is fired through the secondjaw 5602 during a firing stroke. The crossbar 5638 can engage a slot inthe anvil of the first jaw to hold the firing assembly 5630 relative tothe first jaw, and the foot 5644 can engage a slot in the second jaw5602, such as the slot 5656 in the cartridge body 5650, for example, tohold the first jaw relative to the cartridge body 5650. In variousembodiments, the crossbar 5638 and/or the foot 5644 can hold the cuttingedge 5636 of the firing assembly 6530 perpendicular to the deck 5652 ofthe fastener cartridge 5650, for example. Referring primarily to FIGS.93A and 93D, the firing assembly 5630 can engage a sled 5634 in thecartridge body 5650 during the firing stroke. The firing assembly 5630can push the sled 5634 distally during the firing stroke to ejectfasteners from the fastener cavities 5654, for example. In variousembodiments, the sled 5634 can have a camming surface or ramp 5642,which can engage drivers and/or fasteners in the fastener cavities 5654,for example. When the ramp 5642 engages a driver, the ramp 5642 can pushthe driver toward the deck 5652 to eject the corresponding fastener fromthe fastener cavity 5654. Further, in various embodiments, the firingassembly 5630 can cut the tissue thickness compensator 5658 during thefiring stroke.

Referring primarily to FIGS. 93A and 93B, the tissue thicknesscompensator 5658 can include a cartridge contacting surface 5662 (FIG.93A) and a tissue contacting surface 5664 (FIG. 93B). The cartridgecontacting surface 5662 can be positioned against the cartridge deck5652 when the tissue thickness compensator 5658 is secured to thecartridge body 5650 (FIG. 93B), for example. Further, the tissuecontacting surface 5664 can be positioned against tissue when tissue isclamped between the first jaw and the second jaw 5602, for example.Referring primarily to FIG. 93A, the tissue thickness compensator 5658can include a mount 5660. In various embodiments, the mount 5660 can bea rectangular or triangular flap, for example, that can extend from thetissue thickness compensator 5658. Further, the mount 5660 can be acutout portion of the tissue thickness compensator 5658, such that aspace 5666 is left in the tissue thickness compensator 5658 thatcorresponds to the shape of the mount 5660. The mount 5660 can bealigned with the slot 5656 of the cartridge body 5650 when the tissuethickness compensator 5658 is positioned relative to the cartridge body5650, for example. Further, the mount 5660 can extend into the slot 5656when the cartridge contacting surface 5662 of the tissue thicknesscompensator 5658 is positioned adjacent to the deck 5652 of thecartridge body 5650. In various embodiments, the mount 5660 can befriction fit into the slot 5656 when the tissue thickness compensator5658 is secured to the cartridge body 5650. The mount 5660 can hold atleast a portion of the tissue thickness compensator 5658 relative to thecartridge body 5650. For example, when the mount 5660 is friction fit inthe slot 5656, the cartridge contacting surface 5662 can be positionedagainst the deck 5652 of the cartridge body 5650.

In various embodiments, the tissue thickness compensator 5658 caninclude a plurality of mounts 5660, which can be aligned with the slot5656 of the cartridge body 5650. For example, at least one mount 5660can be positioned in the proximal portion 5604 of the second jaw 5602,and at least one mount 5660 can be positioned in the distal portion 5606of the second jaw 5602. In various embodiments, the mounts 5660 can bespaced along at least a portion of the length of the tissue thicknesscompensator 5658. For example, the slot 5656 can be a longitudinal slotthat extends from the proximal portion 5604 to the distal portion 5606of the second jaw 5602. The mounts 5660 can be friction fit into thelongitudinal slot 5656, for example, and can secure the tissue thicknesscompensator 5658 to the cartridge body 5650.

Referring primarily to FIGS. 93A and 93D, the sled 5634 can include atongue 5640, which can project from the sled 5634 toward the distalportion 5606 of the jaw 5602. When the firing assembly 5630 pushes thesled 5634 during the firing stroke, the tongue 5640 can move along theslot 5656 in the cartridge body 5650. Referring primarily to FIG. 93D,the tongue 5640 can move along the slot 5656 adjacent to the cartridgecontacting surface 5664 of the tissue thickness compensator 5658.Further, the tongue 5640 can move against the mounts 5660 that arepositioned in the slot 5656. In various embodiments, the mounts 5660 canbe deflectable. When the tongue 5640 pushes against the mounts 5660, thetongue 5640 can deflect the mounts 5660 into alignment, or at leastsubstantial alignment, with the body of the tissue thickness compensator5658. For example, when the tongue 5640 moves in the cartridge body5650, the mounts 5660 can be sequentially deflected into thecorresponding spaces 5666 defined in the tissue thickness compensator5658. When the mounts 5660 are deflected out of the slot 5656, thetissue thickness compensator 5658 can be unsecured to and/or releasedfrom the cartridge body 5650. In various embodiments, another element ofthe sled 5634 and/or the firing assembly 5630 can deflect the mounts5660 out of the slot 5656 to unsecure and/or release the tissuethickness compensator 5658 from the cartridge body 5650.

Referring now to FIG. 94, an end effector assembly 5700, similar to theend effector assembly 5600, can include a first jaw, illustratedelsewhere, and a second jaw 5702. In various embodiments, the second jaw5702 can include a fastener cartridge body 5750 and a tissue thicknesscompensator 5758 releasably secured to the cartridge body 5750 and/or tothe second jaw 5702. In certain embodiments, the fastener cartridge body5750 and the tissue thickness compensator 5758 releasably securedthereto can comprise a fastener cartridge assembly, for example. Similarto the cartridge body 5650, the cartridge body 5750 can have a cartridgedeck 5752, fastener cavities 5754 defined in the cartridge deck 5752 andfor holding fasteners, ridges 5748 at least partially around thefastener cavities 5754, and/or a slot 5756 extending from a proximalportion 5704 of the second jaw 5702 toward a distal portion 5706 of thesecond jaw 5702. In various embodiments, the cartridge body 5750 caninclude a bridge 5780 traversing or extending across the slot 5756. Thebridge 5780 can be a frangible and/or splitable bridge, for example. Incertain embodiments, the bridge 5780 can be a thin, breakable portion,and can be a solid form absorbable material, such as PGA, PCL, PGA/PCL,PLA/PCL, and/or TMC, for example. The bridge 5780 can have an aperture5782, which can extend at least partially through the bridge 5780.

Referring still to FIG. 94, in various embodiments, the firing assembly5630 can translate along the slot 5756 of the cartridge body 5750. Forexample, the firing assembly 5630 can translate along the slot 5756during a firing stroke, and can eject the fasteners from the fastenercavities 5754 during the firing stroke. The firing assembly 5630 caninclude the firing bar 5632, the cutting edge 5636, the crossbar 5638,and the foot 5644. The cutting edge 5636 can cut tissue and/or cut thetissue thickness compensator 5758 as the firing assembly 5630 is firedthrough the second jaw 5702 during a firing stroke. The crossbar 5638can engage a slot in the anvil of the first jaw to hold the first jawrelative to the cartridge body 5750, and the foot 5644 can engage a slotin the second jaw 5702, such as the slot 5756 in the cartridge body5750, for example, to hold the firing assembly 5630 relative to thesecond jaw 5702. In various embodiments, the crossbar 5638 and/or thefoot 5644 can hold the cutting edge 5636 perpendicular to the deck 5752of the fastener cartridge 5750, for example.

Referring still to FIG. 94, the tissue thickness compensator 5758 caninclude a cartridge contacting surface 5762 and a tissue contactingsurface. The cartridge contacting surface 5762 can be positioned againstthe cartridge deck 5752 when the tissue thickness compensator 5758 issecured to the cartridge body 5750 and/or to the second jaw 5702, forexample. Further, the tissue contacting surface can be positionedagainst tissue when tissue is clamped between the first jaw and thesecond jaw 5702, for example. In various embodiments, the tissuethickness compensator 5758 can include a mount 5760. The mount 5760 canbe a protrusion, pin, tab, and/or post, for example, which can extendfrom cartridge contacting surface 5762 of the tissue thicknesscompensator 5758. The mount 5760 can be aligned, or at leastsubstantially aligned, with the aperture 5782 of the bridge 5780 whenthe tissue thickness compensator 5758 is positioned relative to thecartridge body 5750, for example. Further, the mount 5760 can extend atleast partially into the aperture 5782 when the cartridge contactingsurface 5762 of the tissue thickness compensator 5758 is positionedadjacent to the deck 5752 of the cartridge body 5750. In variousembodiments, the mount 5760 can be friction fit into the aperture 5782when the tissue thickness compensator 5758 is secured to the cartridgebody 5750. The mount 5760 can hold and/or secure the tissue thicknesscompensator 5758 relative to the cartridge body 5750 and/or to thesecond jaw 5702. For example, when the mount 5760 is friction fit in theaperture 5782 of the bridge 5780, the cartridge contacting surface 5762can be positioned against the deck 5752 of the cartridge body 5750.

In various embodiments, the fastener cartridge 5750 can include aplurality of bridges 5780 extending across the slot 5756 of thecartridge body 5750. The bridges 5780 can be spaced along at least aportion of the length of the slot 5756, for example. For example, theslot 5756 can be a longitudinal slot that extends from the proximalportion 5704 to the distal portion 5706 of the second jaw 5702. Further,in various embodiments, the tissue thickness compensator 5758 caninclude a plurality of mounts 5760, which can be aligned with thebridges 5780 of the cartridge body 5750. For example, at least one mount5760 can be positioned in the proximal portion 5704 of the second jaw5702, and at least one mount 5760 can be positioned in the distalportion 5706 of the second jaw 5702 when the tissue thicknesscompensator 5758 is positioned relative to the cartridge body 5750. Invarious embodiments, the mounts 5760 can be spaced along at least aportion of the length of the tissue thickness compensator 5758. Themounts 5760 can be friction fit into the slot 5756, for example, and cansecure the tissue thickness compensator 5758 to the cartridge body 5750and/or to the second jaw 5702.

Referring still to FIG. 94, the cutting edge 5636 of the firing assembly5630 can cut the tissue thickness compensator 5758 and/or tissue clampedbetween the first jaw and the second jaw 5702 of the end effectorassembly 5700 when the firing assembly 5630 moves along the slot 5756during a firing stroke. Further, the firing assembly 5630 can split thebridge 5780 when the firing assembly 5630 moves through the slot 5756.For example, the cutting edge 5636 of the firing assembly 5630 can breakor cut the bridge 5780 when the firing assembly moves through the slot5756. In various embodiments, the cutting edge 5636 can successively cuteach bridge 5780 as the firing assembly 5630 moves in the slot 5756during the firing stroke. When the bridges 5780 are cut or broken by thecutting edge 5636 the tissue thickness compensator 5758 can be unsecuredto and/or released from the cartridge body 5750. In certain embodiments,the cutting edge 5636 can break or cut the mounts 5760 aligned therewithduring a firing stroke. In various embodiments, another element of thesled and/or the firing assembly 5630 can break or cut the bridges 5780to release the tissue thickness compensator 5758 from the cartridge body5750.

Referring now to FIGS. 95 and 96, an end effector assembly 5800, similarto the end effector assembly 5600, can include a first jaw, illustratedelsewhere, and a second jaw 5802. In various embodiments, the second jaw5802 can include a fastener cartridge body 5850 and a tissue thicknesscompensator 5858 releasably secured to the cartridge body 5850 and/or tothe second jaw 5802. In certain embodiments, the fastener cartridge body5850 and the tissue thickness compensator 5858 releasably securedthereto can comprise a fastener cartridge assembly. Similar to thecartridge body 5650, the cartridge body 5850 can have a cartridge deck5852, fastener cavities 5854 defined in the cartridge deck 5852configured to receive fasteners, a ridge 5848 positioned around at leasta portion of a fastener cavity 5854, and a slot 5856, which can extendfrom a proximal portion 5804 of the second jaw 5802 toward a distalportion 5806 of the second jaw 5802. In various embodiments, thecartridge body 5850 can include a bridge 5880 traversing or extending atleast partially across the slot 5856. The bridge 5880 can be a frangibleand/or splitable bridge, for example. In certain embodiments, the bridge5880 can include a first leg 5884 and a second leg 5886. Referringprimarily to FIG. 96, the first leg 5884 can extend from a first side ofthe cartridge body 5850 into the slot 5856, for example, and the secondleg 5886 can extend from a second side of the cartridge body 5850 intothe slot 5856, for example. The first leg 5884 and the second leg 5886can be angularly oriented relative to the axis of the slot 5856, and thefirst leg 5884 can be angularly oriented approximately 90 degreesrelative to the second leg 5886, for example. In certain embodiments,the first leg 5884 and/or the second leg 5886 can deflectable. Invarious embodiments, the bridge 5880 can include a gap between the firstleg 5884 and the second 5886, for example.

Referring still to FIGS. 95 and 96, in various embodiments, the firingassembly 5630 can translate along the slot 5856 of the cartridge body5850. For example, the firing assembly 5630 can translate along the slot5856 during a firing stroke, and can eject the fasteners from thefastener cavities 5854 during the firing stroke. The firing assembly5630 can include the firing bar 5632, the cutting edge 5636, thecrossbar 5638, and the foot 5644. The cutting edge 5636 can cut tissueand/or cut the tissue thickness compensator 5858 as the firing assembly5630 is fired through the second jaw 5802 during a firing stroke. Thecrossbar 5638 can engage a slot in the anvil of the first jaw to holdthe first jaw relative to the cartridge body 5850, and the foot 5644 canengage a slot in the second jaw 5802, such as the slot 5856 in thecartridge body 5850, for example, to hold the firing assembly 5630relative to the second jaw 5802. In various embodiments, the crossbar5638 and/or the foot 5644 can hold the cutting edge 5636 perpendicularto the deck 5852 of the fastener cartridge 5850, for example.

Referring still to FIGS. 95 and 96, the tissue thickness compensator5858 can include a cartridge contacting surface 5862 and a tissuecontacting surface. The cartridge contacting surface 5862 can bepositioned against the cartridge deck 5852 when the tissue thicknesscompensator 5858 is secured to the cartridge body 5850 and/or to thesecond jaw 5802, for example. Further, the tissue contacting surface canbe positioned against tissue when tissue is clamped between the firstjaw and the second jaw 5802, for example. In various embodiments, thetissue thickness compensator 5858 can include a mount 5860. Similar tothe mount 5760, the mount 5860 can be a protrusion, pin, tab, and/orpost, for example, which can extend from the cartridge contactingsurface 5862 of the tissue thickness compensator 5858. The mount 5860can be aligned with the gap between the legs 5884, 5886 of the bridge5880 when the tissue thickness compensator 5858 is positioned relativeto the cartridge body 5850, for example. Further, the mount 5860 can beheld by the legs 5884, 5886 of the bridge 5880 when the cartridgecontacting surface 5862 of the tissue thickness compensator 5858 ispositioned adjacent to the deck 5852 of the cartridge body 5850. Invarious embodiments, the mount 5860 can be friction fit into the gapbetween the legs 5884, 5886 when the tissue thickness compensator 5858is secured to the cartridge body 5850. The mount-bridge engagement ofthe second jaw 5802 can hold the tissue thickness compensator 5858relative to the cartridge body 5850. For example, when the mount 5860 isfriction fit between the legs 5884, 5886 of the bridge 5880, thecartridge contacting surface 5862 can be held against the deck 5852 ofthe cartridge body 5850.

In various embodiments, referring primarily to FIG. 95, the fastenercartridge 5850 can include a plurality of bridges 5880 extending acrossthe slot 5856 of the cartridge body 5850. The bridges 5880 can be spacedalong at least a portion of the length of the slot 5856, for example.For example, the slot 5856 can be a longitudinal slot that extends fromthe proximal portion 5804 to the distal portion 5806 of the second jaw5802. Further, in various embodiments, the tissue thickness compensator5858 can include a plurality of mounts 5860, which can be aligned withthe bridges 5880 of the cartridge body 5850. For example, at least onemount 5860 can be positioned in the proximal portion 5804 of the secondjaw 5802, and at least one mount 5860 can be positioned in the distalportion 5806 of the second jaw 5802 when the tissue thicknesscompensator 5858 is positioned relative to the cartridge body 5850and/or the second jaw 5802. In various embodiments, the mounts 5860 canbe spaced along at least a portion of the length of the tissue thicknesscompensator 5858. The mounts 5860 can be friction fit into the bridges5880, for example, and can secure the tissue thickness compensator 5858to the cartridge body 5850.

Referring still to FIGS. 95 and 96, the cutting edge 5636 of the firingassembly 5630 can cut the tissue thickness compensator 5858 and/or thetissue clamped between the first jaw and the second jaw 5802 of the endeffector assembly 5800 when the firing assembly 5630 moves along theslot 5856 during a firing stroke. Further, the firing assembly 5630 cansplit the bridge 5880 when the firing assembly 5630 moves through theslot 5856. For example, the cutting edge 5636 of the firing assembly5630 can deflect and/or split the legs 5884, 5886 of the bridge 5880when the firing assembly 5630 moves through the slot 5856. In variousembodiments, the cutting edge 5636 can successively deflect the legs5884, 5886 of each bridge 5880 to split each bridge 5880 as the firingassembly 5630 moves in the slot 5856 during the firing stroke. When thelegs 5884, 5886 of a bridge 5880 are deflected by the cutting edge 5636,the bridge 5880 can release the corresponding mount 5860 of the tissuethickness compensator 5858. The tissue thickness compensator 5858 can beunsecured to and/or released from the cartridge body 5850 when eachmount 5860 is released from each bridge 5880 along the length of thecartridge body 5850. In certain embodiments, the cutting edge 5636 cancut or break the mounts 5860 aligned therewith during a firing stroke.In various embodiments, another element of the sled and/or the firingassembly 5630 can split the bridges 5880 to release the tissue thicknesscompensator 5858 from the cartridge body 5850.

Referring now to FIGS. 97-100, an end effector assembly 5900, similar tothe end effector assembly 5600, can include a first jaw or anvil 5910(FIGS. 99 and 100) and a second jaw 5902. In various embodiments, thesecond jaw 5902 can include a fastener cartridge body 5950 and a tissuethickness compensator 5958 releasably secured to the fastener cartridgebody 5950 and/or to the second jaw 5902. In certain embodiments, thefastener cartridge body 5950 and the tissue thickness compensator 5958releasably secured thereto can comprise a fastener cartridge assembly,for example. Referring primarily to FIG. 98, the fastener cartridge body5950 can have a cartridge deck 5952 and cavities defined in thecartridge deck 5962. Mount cavities 5948 and/or fastener cavities 5954can be defined in the cartridge deck 5952, for example. In variousembodiments, the mount cavities 5948 and the fastener cavities 5954 canhave the same or similar structure and/or geometry. The second jaw 5902can include fasteners, such as surgical staples, for example, which canbe removably positioned in the fastener cavities 5954. In certainembodiments, the cartridge body 5950 can include a slot 5956, which canextend from a proximal portion 5904 of the second jaw 5902 toward adistal portion 5906 of the second jaw 5902.

Referring still to FIGS. 97-100, in various embodiments, the firingassembly 5630 can translate along the slot 5956 of the cartridge body5950 during a firing stroke, and can eject the fasteners from thefastener cavities 5954 during the firing stroke. The cutting edge 5636can cut tissue and/or cut the tissue thickness compensator 5958 as thefiring assembly 5630 is fired through the end effector assembly 5900during the firing stroke. The crossbar 5638 can engage a slot 5912 inthe anvil 5910 (FIGS. 99 and 100) to hold the first jaw relative to thecartridge body 5950, and the foot 5644 can engage a slot in the secondjaw 5902, such as the slot 5956 in the cartridge body 5950, for example,to hold the firing assembly 5630 relative to the second jaw 5902. Invarious embodiments, the crossbar 5638 and/or the foot 5644 can hold thecutting edge 5636 perpendicular to the deck 5952 of the fastenercartridge 5950, for example.

Referring still to FIGS. 97-100, the tissue thickness compensator 5958can include a cartridge contacting surface 5962 (FIG. 97) and a tissuecontacting surface 5964 (FIGS. 98 and 99). The cartridge contactingsurface 5962 can be positioned against the cartridge deck 5952 when thetissue thickness compensator 5958 is secured to the cartridge body 5950and/or to the second jaw 5902, for example. Further, the tissuecontacting surface 5964 can be positioned against tissue when tissue isclamped between the anvil 5910 and the second jaw 5902, for example. Invarious embodiments, the tissue thickness compensator 5958 can include amount 5960. Similar to the mount 5760 and/or the mount 5860, forexample, the mount 5960 can be a protrusion, pin, tab, and/or post, forexample, which can extend from the cartridge contacting surface 5962 ofthe tissue thickness compensator 5958. In certain embodiments, thetissue thickness compensator 5958 can include a recess 5970, which canbe adjacent to the mount 5960, for example. The recess 5970 can bevertically aligned with the mount 5970, for example. Referring primarilyto FIG. 99, the recess 5970 can be defined in the tissue contactingsurface 5964 of the tissue thickness compensator 5958, and can extendtoward the mount 5960. In various embodiments, a thin piece of thetissue thickness compensator 5958 can be positioned between the recess5970 and the mount 5960, for example.

The mount 5960 can be aligned with a mount cavity 5948 in the cartridgedeck 5952 when the tissue thickness compensator 5958 is positionedrelative to the cartridge body 5950, for example. Further, the mount5960 can be positioned in the mount cavity 5948 when the cartridgecontacting surface 5962 of the tissue thickness compensator 5958 ispositioned adjacent to the deck 5952 of the cartridge body 5950. Invarious embodiments, the mount 5960 can be friction fit into the mountcavity 5948 when the tissue thickness compensator 5958 is secured to thecartridge body 5950. The friction fit engagement between the mount 5960and the mount cavity 5948 can hold at least a portion of the tissuethickness compensator 5958 relative to the cartridge body 5950. Forexample, when the mount 5960 is friction fit in the mount cavity 5948,the cartridge contacting surface 5962 can be held against the deck 5952of the cartridge body 5950.

Referring primarily to FIGS. 97 and 98, the fastener cartridge 5950 caninclude a plurality of mount cavities 5948 defined in the cartridge deck5952. In certain embodiments, corresponding mount cavities 5948 can bedefined in the cartridge deck 5952 on either side of the slot 5956. Afirst mount cavity 5948 can be defined on a first longitudinal side ofthe cartridge body 5950, for example, and a corresponding second mountcavity 5948 can be defined on a second longitudinal side of thecartridge body 5950, for example. A first pair of corresponding mountcavities 5948 can be positioned in the proximal portion 5904 of thesecond jaw 5902 and/or a second pair of corresponding mount cavities5948 can be positioned in the distal portion 5906 of the second jaw5902, for example. In various embodiments, fastener cavities 5954 can bepositioned between the corresponding pairs of mount cavities 5948, i.e.,closer to the slot 5956, and between the pair of mount cavities 5948 atthe proximal portion 5904 of the second jaw 5902 and the pair of mountcavities 5948 at the distal portion 5906 of the second jaw 5902, i.e.,in an intermediate portion of the cartridge body 5950. Further, invarious embodiments, the tissue thickness compensator 5958 can include aplurality of mounts 5960, which can be aligned with the mount cavities5948 of the cartridge body 5950. For example, at least one mount 5960can be positioned in the proximal portion 5904 of the second jaw 5902,and at least one mount 5960 can be positioned in the distal portion 5906of the second jaw 5902. In various embodiments, a pair of mounts 5960can be positioned in the proximal portion 5904 of the second jaw 5902,and a pair of mounts 5960 can be positioned in the distal portion 5906of the second jaw 5902. The mounts 5960 can be friction fit into mountcavities 5948, for example, and can secure at least a portion of thetissue thickness compensator 5958 to the cartridge body 5950.

Referring primarily to FIGS. 99 and 100, the mounts 5960 can be removedfrom the mount cavities 5948 during a firing stroke. In variousembodiments, drivers 5920 movably positioned in the mount cavities 5948can eject the mounts 5960 from the mount cavities 5948 during the firingstroke. For example, a driver 5920 can be positioned in each mountcavity 5948. During a firing stroke, an element of the firing assembly5630 and/or a sled in the second jaw 5902 can engage the driver 5920 tomove the driver 5920 toward the cartridge deck 5952 and/or toward thetissue thickness compensator 5958, for example. As the driver 5920moves, the driver 5920 can push the mount 5960 positioned in the mountcavity 5948 toward the deck 5952 and/or toward the tissue thicknesscompensator 5958, for example. In various embodiments, the recess 5970defined in the tissue thickness compensator 5958 that corresponds to thepushed mount 5960 can receive the pushed mount 5960. For example, thedriver 5920 can push the mount 5960 into the recess 5970. The mount 5960can be crushed, deformed and/or compressed into the recess 5970, forexample. When the mounts 5960 are removed from the mount cavities 5960during the firing stroke and pushed into the corresponding recesses5970, the tissue thickness compensator 5958 can be unsecured and/orreleased from the cartridge body 5950.

In various embodiments, referring now to FIGS. 62-66, a staple cartridge13000 can comprise a cartridge body 13010, a tissue thicknesscompensator 13020, and a plurality of firable connectors configured toreleasably hold the tissue thickness compensator 13020 to the cartridgebody 13010, as described in greater detail further below. The cartridgebody 13010 can comprise a proximal end 13011, a distal end 13012, and adeck 13015 configured to support the tissue thickness compensator 13020thereon. The cartridge body 13010 can include one or more proximal stops13013 extending therefrom which can be configured to block or resist theproximal movement of the tissue thickness compensator 13020. Similarly,the cartridge body 13010 can include one or more distal stops 13014which can be configured to block or resist the distal movement of thetissue thickness compensator 13020. Referring primarily to FIG. 63, thecartridge body 13010 can further comprise a plurality of staple cavities13016 defined therein. In various embodiments, the staple cartridge13000 can comprise a plurality of connectors 13030 and 13040 configuredto releasably hold the tissue thickness compensator 13020 to thecartridge body 13010. Each connector 13030, for example, can comprise aplurality of cavity plugs 13031, which are positionable in the staplecavities 13016, and a connecting bar 13032 extending between the cavityplugs 13031 and over the tissue thickness compensator 13020. The cavityplugs 13031, in at least one embodiment, can fit snugly within thestaple cavities 13016. In certain embodiments, the cavity plugs 13031can be press-fit and/or snap-fit into the staple cavities 13016. Eachconnector 13040, for example, can comprise a cavity plug 13031 and ahead 13042 extending therefrom, wherein the head 13042 can at leastpartially extend over the tissue thickness compensator 13020. Referringagain to FIG. 63, the tissue thickness compensator 13020 can comprise aset of proximal notches 13023 defined in the proximal end 13021 of thetissue thickness compensator 13020 configured to receive the cavityplugs 13031 extending from a proximal connector 13030, intermediatenotches 13024 each configured to receive a cavity plug 13031 extendingfrom intermediate connectors 13040, and a set of distal notches 13025defined in the distal end 13022 of the tissue thickness compensator13020 configured to receive the cavity plugs 13031 extending from adistal connector 13030, for example.

In use, a sled, or firing member, can be advanced distally through thestaple cartridge 13000 to eject staples positioned within the staplecavities 13016. In various embodiments, the staple cavities 13016comprising a staple positioned therein may not be plugged by a cavityplug 13031. In certain embodiments, the staple cavities having a cavityplug 13031 positioned therein may not have a staple positioned therein.In some embodiments, although not illustrated, a staple cavity mayinclude a fastener and a cavity plug 13031 positioned therein. Referringagain to FIGS. 65 and 66, the staple cartridge 13000 may furthercomprise a plurality of staple drivers 13050, for example, which supportthe staples in their unfired position. As the firing member, forexample, is advanced distally through the staple cartridge, the firingmember can lift the staple drivers 13050 and the staples upwardly, i.e.,toward the deck 13015 of the cartridge body 13010 and toward an anvilpositioned opposite the tissue thickness compensator 13020. Similarly,at least some of the staple drivers 13050 can contact and lift thecavity plugs 13031 positioned in some of the staple cavities 13016upwardly toward the anvil. When the staples are lifted upwardly by thestaple drivers 13050, the legs of the staples can pass through thetissue thickness compensator 13020, through tissue positioned betweenthe tissue thickness compensator 13020 and the anvil, and contact theanvil positioned on the opposite side of the tissue. The staple drivers13050 can then drive the staples against the anvil such that the staplesare deformed to capture the tissue thickness compensator 13020 and thetissue therein. When the cavity plugs 13031 are lifted upwardly by thestaple drivers 13050, the anvil may resist the upward movement of thecavity plugs 13031. In such circumstances, referring primarily to FIG.63, the cavity plugs 13031 may deform, deflect, and/or break. In certainembodiments, the cavity plugs 13031 can include one or more notches, forexample, which can induce the deformation, deflection, and/or breakageof the cavity plugs 13031 at a specific location therein. In variouscircumstances, the entirety, or at least substantial entirety, of thecavity plugs 13031 may be ejected from the staple cavities 13016 by thestaple drivers 13050. At such point, the connectors 13030 and/or 13040may no longer connect the tissue thickness compensator 13020 to thecartridge body 13010 and, as such, the cartridge body 13010 can be movedaway the tissue thickness compensator 13020 that has been implantedagainst the tissue.

In use, further to the above, the firing member can be advanced from theproximal end 13011 toward the distal end 13012 of the staple cartridge13000. The cartridge body 13010 can include a longitudinal slot 13019configured to slidably receive at least a portion of the firing membertherein. As the firing member is advanced distally, the firing membercan eject the staples positioned in the proximal-most staples 13016 and,then, fire the proximal-most connector 13030. The firing of theproximal-most connector 13030 can release the proximal end 13021 of thetissue thickness compensator 13020 from the cartridge body 13010. Inother embodiments, the firing member can fire the proximal-mostconnector prior to firing any staples. In any event, the firing membercan be further advanced distally to eject staples from the staplecavities 13016 and then fire the intermediate connectors 13040. At suchpoint, only the distal-most connector 13030 may remain which holds thetissue thickness compensator 13020 to the cartridge body 13010. Once thefiring member has fired the distal-most connector 13030, the tissuethickness compensator 13020 may no longer be attached to the cartridgebody 13010. The above-described sequence describes a staple cartridgewhich is fully or completely fired. Other circumstances can arise inwhich less than the entirety of the staples contained in the staplecartridge are fired. In such circumstances, some of the connectorsholding the tissue thickness compensator 13020 to the cartridge body13010 may not be fired. When the partial use of the staple cartridge13000 is complete, the anvil may be opened and the cartridge body 13010may be pulled away from the partially implanted tissue thicknesscompensator 13020. In such circumstances, the unfired connectors may beconfigured to slide out of the staple cavities 13016 even though theyhave not been fired. In any event, the connectors 13030 and 13040, forexample, may be comprised of any suitable biocompatible and/orbioabsorbable material.

Further to the above, the firing member may include a cutting portion,such as a knife, for example, which can be configured to transect thetissue thickness compensator 13020 and the tissue as the firing memberis advanced distally through the staple cartridge 13000. In suchcircumstances, the cutting portion can also be configured to transectthe connecting bars 13032 of the connectors 13030.

In various embodiments, referring now to FIGS. 101 and 102, a staplecartridge 10800 comprising a support portion 10810 and a tissuethickness compensator 10820 can be loaded into a staple cartridgechannel with a staple cartridge applicator 10880, for example. Similarto the above, the staple cartridge applicator 10880 can also beconfigured to position an upper tissue thickness compensator 10890, forexample, relative to an anvil, such as anvil 10060, for example, suchthat, when the anvil 10060 is closed, the anvil 10060 can contact andengage the tissue thickness compensator 10890. In at least oneembodiment, the tissue thickness compensator 10890 can comprise aplurality of retention legs 10895 extending from the top surface 10891of the tissue thickness compensator 10890 which can be configured to beengage the anvil 10060 and releasably retain the tissue thicknesscompensator 10890 to the anvil 10060. In at least one such embodiment,the legs 10895 can be arranged in a longitudinal row wherein each leg10895 can comprise at least one foot configured to enter into and engagethe knife slot 10065 defined in the anvil 10060. In certain embodiments,some of the feet of legs 10895 can extend in one direction while otherfeet can extend in another direction. In at least one embodiment, someof the feet can extend in opposite directions.

In any event, once the anvil 10060 has been engaged with the tissuethickness compensator 10890, referring now to FIGS. 102 and 103, theanvil 10060 can be reopened and the clinician can move the staplecartridge applicator 10880 away from the tissue thickness compensators10820 and 10890. Thereafter, referring to FIG. 104, the upper tissuethickness compensator 10890 can be positioned on a first side of thetargeted tissue and the tissue thickness compensator 10820, which cancomprise a lower tissue thickness compensator, can be positioned on asecond side of the tissue. After the tissue thickness compensators 10820and 10890 have been suitably positioned, referring now to FIG. 105, aknife edge of a firing member, such as knife edge 10053, for example,can be advanced through the tissue and the tissue thicknesscompensators.

In various embodiments, referring now to FIG. 106, a staple cartridgeapplicator, such as applicator 12280, for example, can comprise a tissuethickness compensator 12290 detachably mounted thereto which can be,similar to the above, inserted into a staple cartridge channel, asillustrated in FIG. 106A, and engaged by the anvil 10060 when the anvil10060 is moved into a closed position. The applicator 12280 may includea handle 10084 for positioning the compensator 12290 relative to astaple cartridge. In addition, the applicator 10084 may comprise aplurality of legs 10081 that may secure the compensator 12290 to thestaple cartridge. In at least one such embodiment, the tissue thicknesscompensator 12290 can comprise a plurality of retention members 12295extending upwardly from the top surface 12291 of the tissue thicknesscompensator 12290 wherein each retention member 12295 can comprise aplurality of flexible legs 12296 which can be configured to be insertedinto the knife slot 10065 in the anvil 10060. Referring primarily toFIGS. 107 and 108, the flexible legs 12296 of each retention member12295 can be separated by a gap 12298 such that, as the legs 12296 areinserted into the knife slot 10065, the legs 12296 can flex inwardly andthen resiliently return outwardly once the enlarged feet of the flexiblelegs 12296 have passed through the knife slot 10065. In variousembodiments, the enlarged feet of the flexible legs 12296 can flexbehind opposing retention lips 12297 defined in the anvil 10060 and, asa result of the interaction of the legs 12296 and the lips 12297, thetissue thickness compensator 12290 can be retained to the anvil 10060.Thereafter, the staple cartridge applicator 12280 can be moved away fromthe tissue thickness compensator 12290, as illustrated in FIG. 106B. Inuse, once the tissue thickness compensator 12290 has been implantedagainst the tissue by staples deployed from staple cartridge 10000, forexample, the anvil 10060 can be re-opened and, as the anvil 10060 ismoved away from the implanted tissue thickness compensator 12290, thelegs 12296 of the retention members 12995 can flex inwardly such thatthey can be pulled out of the knife slot 10065.

As outlined above, an end-effector assembly can include a staplecartridge, an anvil, and at least one piece of buttress materialpositioned intermediate the staple cartridge and the anvil. In at leastone embodiment, referring now to FIGS. 109-111, a piece of buttressmaterial, such as buttress material 336, can be configured to besnap-fit to at least one of staple cartridge 322 and/or an anvil (notillustrated) to releasably retain the piece of buttress material withinthe end effector. Referring to FIGS. 110 and 111, staple cartridge 322can include first side wall 302 and second side wall 304, wherein atleast one of the first and second side walls can include a lip 306extending outwardly therefrom. In various embodiments, buttress material336 can include first edge, or side, 308, second edge, or side, 310, andat least one lip 312 extending at least partially along the length ofedges 308 and 310. In at least one embodiment, referring to FIG. 111,lips 312 can be configured to engage lips 306 in a snap-fit fashion inorder to releasably retain buttress material 336 to staple cartridge322.

Further to the above, referring to FIG. 111, buttress material 336 caninclude surface 316 which can be configured to be positioned adjacent toor against deck 328 of staple cartridge 322. In at least one embodiment,side edges 308 and 310 can comprise sidewalls which can extend in aperpendicular or transverse direction relative to surface 316. In suchembodiments, lips 312 can extend from these sidewalls such that lips 312can be interlocked behind lips 306 of staple cartridge 322. In variousembodiments, lips 312 of buttress material 336 can be disengaged fromlips 306 of staple cartridge 322 when the staples are deployed fromstaple cartridge 322. More particularly, when the staples are deployed,the staples can contact buttress material 336, apply an upward force tobuttress material 336, and dislodge buttress material 336 from staplecartridge 322. Advantageously, as a result, buttress material 336 may beautomatically disengaged from staple cartridge 322 when the staples aredeployed therefrom and/or when the end-effector is opened as describedabove.

In various embodiments, referring to FIGS. 110 and 111, a piece ofbuttress material can include at least one member extending therefromwhich can be configured to releasably retain the buttress material toone of a staple cartridge and/or an anvil. In at least one embodiment,member 318 can extend from buttress material 336 in a direction which isperpendicular or transverse to surface 316. In various embodiments,member 318 can be engaged with one of staple cavity 320, and/or an anvilpocket, in a friction-fit or press-fit manner to releasably retain thepiece of buttress material to one of the staple cartridge and the anvil.Similar to the above, in various embodiments, staples deployed fromstaple cavities 320 can apply an upward force to buttress material 336and disengage members 318 from staple cavities 320. In variousembodiments, the staples can pierce members 318 and/or buttress material336 to secure the buttress material to the tissue as outlined above.

As illustrated in FIG. 110, a piece of buttress material can includemore than one member, or projection, extending therefrom to retain apiece of buttress material to one of a staple cartridge and an anvil. Invarious embodiments, referring now to FIGS. 112 and 113, more than onemember 318′ can extend from piece of buttress material 336′, forexample. In at least one embodiment, members 318′ can be can press-fitinto staple cavities 320′ of staple cartridge 322′, and/or into anvilpockets of an anvil (not illustrated), such that the members canfrictionally retain the piece of buttress material to the staplecartridge and/or the anvil as outlined above. As described in greaterdetail herein, a staple cartridge and/or anvil can include slots orapertures therein in addition to the staple cavities of the staplecartridge and the anvil pockets of the anvil for receiving projections,or retaining members, extending from a piece of buttress material.

In certain embodiments, as described in greater detail below, a supportportion can comprise retention features, which can be configured toprogressively release a tissue thickness compensator from the supportportion as the staples are progressively fired from the staplecartridge. Referring now to FIG. 114, a staple cartridge, such as staplecartridge 11200, for example, can comprise a support portion 11210including retention features 11213 which can be configured to releasablyhold a tissue thickness compensator 11220 (FIG. 115) to the supportportion 11210. In various embodiments, the retention features 11213 canbe positioned at the ends of each staple cavity 11212, for example,wherein each retention feature 11213 can comprise a guide groove 11216defined therein which is configured to slidably receive a staple leg10032 of a staple 10030. In such embodiments, both the staple legs 10032and the retention features 11213 can be configured to releasably retainthe tissue thickness compensator 11220 to the support portion 11210.

In use, referring now to FIG. 115, staple drivers 10040 contained withinthe support portion 11210 can be driven upwardly by a sled 10050, asdescribed above, wherein the staple drivers 10040 can be configured tocontact the retention features 11213, at least partially detach theretention features 11213 from the support portion 11210, and displacethe retention features 11213 outwardly and away from the staples 10030and the staple cavities 11212. When the retention features 11213 aredetached from the support portion 11210 and/or displaced outwardly, theretention features 11213 may no longer be able to retain the tissuethickness compensator 11220 to the support portion 11210 and, as aresult, the tissue thickness compensator 11220 can be released from thesupport portion 11210. Similar to the above, the tissue thicknesscompensator 11220 can be progressively released from the support portion11210 as the staples 10030 are progressively ejected from the staplecartridge toward an anvil, such as anvil 11260, for example. In variousembodiments, the staple drivers 10040 may contact the retention features11213 when the top surfaces of the staple drivers 10040 becomeco-planar, or at least substantially co-planar, with the deck surface11211 of the support portion 11210, for example. In such embodiments,the tissue thickness compensator 11220 may be released from the supportportion 11210 at the same time as and/or just before the staples 10030are formed to their fully-formed, or fully-fired, configuration.

In at least one such embodiment, referring primarily to FIG. 116, thedrivers 10040 can be overdriven such that they are pushed above the decksurface 11211 to fully form the staples 10030 and, during the process ofbeing overdriven, break the retention features 11213 away from thesupport portion 11210. In various embodiments, referring again to FIG.115, the retention features 11213 may extend over, or overhang, into thestaple cavities 11212 prior to being detached or displaced outwardlysuch that the drivers 10040 can contact the retention features 11213just as the drivers 10040 reach the deck surface 11211. In any event,once the tissue thickness compensator 11220 has been released from thesupport portion 11210, referring now to FIG. 116, the support portion11210 can be moved away from the implanted tissue thickness compensator11220.

Referring now to FIG. 117, a fastener cartridge assembly 6002 for usewith an end effector assembly can include a cartridge body 6050 and atissue thickness compensator 6058 releasably secured thereto. Similar tothe cartridge body 5650, for example, the cartridge body 6050 caninclude a slot 6056 configured to guide a firing assembly and/orfastener cavities 6054 configured to removably retain fasteners in thecartridge body 6050. In various embodiments, the cartridge body 6050 caninclude a projection 6048, such as a post, mount, tab, and/or ridge, forexample. The projection 6048 can extend from the cartridge deck of thecartridge body 6050 and into the tissue thickness compensator 6058 whenthe tissue thickness compensator 6058 is positioned relative to thecartridge deck. In various embodiments, the cartridge body 6050 caninclude a plurality of projections 6048 extending from the cartridgedeck. The projections 6048 can be positioned along the length of thecartridge body 6050, for example, and can be positioned between adjacentfastener cavities 6054, for example.

Referring still the FIG. 117, in various embodiments, the tissuethickness compensator 6058 can be thermoformed around the projections6048 of the tissue thickness compensator 6058. For example, the tissuethickness compensator 6058 can be positioned relative to the cartridgedeck of the cartridge body 6050. Once positioned, the tissue thicknesscompensator 6058 can be heated to a sufficient temperature such that thetissue thickness compensator 6058 deforms to accommodate the shape ofthe cartridge deck, including the shape of the projections 6048extending therefrom. The tissue thickness compensator 6058 can belocally heated, for example, and can reach a temperature near and/orapproaching the glass transition temperature of the material comprisingthe tissue thickness compensator 6058, for example. The tissue thicknesscompensator can be heated to approximately 90 degrees C. toapproximately 120 degrees C., for example. In certain embodiments, thetissue thickness compensator can be heated to approximately 75 degreesC. to approximately 150 degrees C., for example. Once the tissuethickness compensator 6058 has deformed to fit around the projections6048, the heat source can be removed or reduced and the tissue thicknesscompensator 6058 can cool. The tissue thickness compensator 6058 can besubjected to the heightened temperature for approximately 2 seconds toapproximately 5 seconds, for example, to attain sufficient deformationaround the projections 6048. In other circumstances, the tissuethickness compensator 6058 can be subjected to the heightenedtemperature for approximately 1 second to approximately 10 seconds, forexample, to attain sufficient deformation around the projections 6048.When cooling, the tissue thickness compensator 6058 can shrink closertoward and/or tighter around the projections 6048, for example. Invarious embodiments, the thermoformed tissue thickness compensator 6058can prevent and/or limit lateral shifting and/or buckling of the tissuethickness compensator 6058 between fastener cavities 6054 and along thelength of the cartridge body 6050.

Additionally or alternatively, the tissue thickness compensator 6058 canbe thermoformed around at least a portion of a fastener removablypositioned in a fastener cavity 6054. For example, the tissue thicknesscompensator 6058 can be thermoformed around the legs of staplesextending above the cartridge deck. Referring still to FIG. 117, invarious embodiments, the fastener cartridge assembly 6002 can include acover or shell 6060 around at least a portion of the cartridge body6050. The shell 6060 can extend around the bottom, sides, and/orcartridge deck of the cartridge body 6050, for example. The shell 6060can be secured to the cartridge body 6050 by pins 6062, for example.Further, in various embodiments, the shell 6060 can include a metallicmaterial, such as stainless steel 300 series, stainless steel 400series, titanium, and/or medical grade aluminum, for example. Themetallic shell 6060 can facilitate heat transfer in the cartridge body6050 and/or the projections 6048 to improve the thermoforming effect,for example.

Referring now to FIG. 118, a fastener cartridge assembly 6102 for usewith an end effector assembly can include a cartridge body 6150 and atissue thickness compensator 6158 releasably secured thereto. Similar tothe cartridge body 5650, the cartridge body 6150 can include a slot 6156configured to guide a firing assembly, for example, and fastenercavities 6154 configured to removably hold fasteners in the cartridgebody 6150, for example. The cartridge body 6150 can also include a ridge6146, similar to the ridge 5648, extending from the cartridge deck 6152.The ridge 6146 can extend around at least a portion of a fastener cavity6154, for example. In various embodiments, when a fastener is positionedin a fastener cavity 6154, the tip of the fastener can protrude from thefastener cavity 6148. In such embodiments, the ridge 6146 positioned atleast partially around the fastener cavity 6154 can support and/or guidethe tip of the fastener when the fastener is ejected from the fastenercavity 6154. In various embodiments, the cartridge body 6150 can includea plurality of ridges 6146 at least partially surrounding the fastenercavities 6154. For example, a ridge 6146 can extend around at least theproximal and/or distal ends of each fastener cavity 6154.

Referring still to FIG. 118, in various embodiments, the fastenercartridge assembly 6102 can include a cover or shell 6160, similar toshell 6060, for example, positioned around at least a portion of thecartridge body 6150. The shell 6160 can extend around the bottom and/orsides of the cartridge body 6150, for example, and can be secured to thecartridge body 6150 by pins 6162, for example. In various embodiments,the shell 6160 can include a projection 6148, such as a post, mount,tab, and/or ridge, for example. The projection 6148 can extend beyondthe cartridge deck 6152 of the cartridge body 6150. In variousembodiments, the projection 6148 can extend into the tissue thicknesscompensator 6158 when the tissue thickness compensator 6158 ispositioned relative to the cartridge deck. In various embodiments, theshell 6160 can include a plurality of projections 6148 extendingtherefrom. The projections 6148 can be positioned along the length ofthe shell 6160, for example, and around the perimeter of the cartridgebody 6150, for example.

Similar to the tissue thickness compensator 6058, the tissue thicknesscompensator 6158 can be thermoformed around the projections 6148 of theshell 6160. In various embodiments, the tissue thickness compensator6158 can be wider than the shell 6160 such that a portion of the tissuethickness compensator 6158 extends beyond the perimeter of the cartridgebody 6150. In such embodiments, the tissue thickness compensator 6158can be thermoformed to the projections 6148 around the perimeter of thecartridge body 6150, for example. Additionally or alternatively, thetissue thickness compensator 6158 can be thermoformed to the ridges 6146and/or to the staple legs extending from the fastener cavities 6154, forexample. In various embodiments, the shell 6160 can include a metallicmaterial, such as such as stainless steel 300 series, stainless steel400 series, titanium, and/or medical grade aluminum, for example, tofacilitate heat transfer and improve the thermoforming effect.

Referring now to FIGS. 119 and 120, an end effector assembly 6200 caninclude a first jaw or anvil 6210 and a second jaw 6202. The second jaw6202 can include a cartridge body 6250 and a tissue thicknesscompensator 6258 releasably secured thereto. Similar to the cartridgebody 5650, the cartridge body 6250 can include fastener cavities 6254and fasteners, such as surgical staples, for example, which can beremovably positioned therein. In various embodiments, a surgical staple6290 can be positioned on a driver 6220 in a fastener cavity 6254.Referring primarily to FIG. 119, when the driver 6220 is in a pre-firedposition, a portion of the staple 6290 can be positioned in the fastenercavity 6254. In various embodiments, the staple 6290 can include a base6292 and legs 6294 a, 6294 b extending from the base 6292. The first leg6294 a can extend from a first end of the base 6292, for example, and asecond leg 6294 b can extend from a second end of the base 6292, forexample. In various embodiments, when the driver 6220 is in a pre-firedposition and the staple 6290 is in a pre-formed configuration, the base6292 of the staple 6290 can be positioned in the fastener cavity 6254and the legs 6294 a, 6294 b of the staple 6290 can extend from thefastener cavity 6254 into the tissue thickness compensator 6258.

In various embodiments, referring still to FIGS. 119 and 120, the staplelegs 6294 a, 6294 b can include a barb between the base 6292 and thetips 6299 a, 6299 b of each staple leg 6294 a, 6294 b. The barb can be asharp and/or pointed protrusion, such as a thorn, for example. Invarious embodiments, wire diameter of staples can be approximately0.0069″, approximately 0.0079″, and/or approximately 0.0089″, forexample. The barb can be approximately 0.001″, for example. In certaincircumstances, the barb can be between approximately 0.0005″ toapproximately 0.003″, for example. In certain embodiments, a first lowerbarb 6296 a can be positioned on the first staple leg 6294 a and asecond lower barb 6296 b can be positioned on the second staple leg 6294b. Lower barbs 6296 a. 6296 b can be positioned between the base 6292and the tips 6299 a, 6299 b of the staple legs 6294 a, 6294 b. Further,a first upper barb 6298 a can be positioned on the first staple leg 6294a and a second upper barb 6298 b can be positioned on the second stapleleg 6294 b. Upper barbs 6298 a, 6298 b can be positioned between thelower barbs 6296 a, 6296 b and the tips 6299 a, 6299 b on the respectivestaple legs 6294 a, 6294 b. When the driver 6220 is in a pre-firedposition and the staple 6290 is in a pre-formed configuration, at leastone barb 6296 a, 6296 b, 6298 a, 6298 b of the staple 6290 can bepositioned in the tissue thickness compensator 6258. In suchembodiments, the barb 6296 a, 6296 b, 6298 a, 6298 b can grip and/orhold the tissue thickness compensator 6258 relative to the cartridgebody 6250, for example. The barb 6296 a, 6296 b, 6298 a, 6298 b embeddedin the tissue thickness compensator 6258 can prevent and/or limitlateral movement of the tissue thickness compensator 6258 relative tothe cartridge deck, for example, and/or can prevent lifting of thetissue thickness compensator 6258 away from the cartridge deck, forexample. Additionally or alternatively, in various embodiments, a barbcan positioned at the tips 6299 a, 6299 b of the staple legs 6294 a,6294 b.

Referring primarily to FIG. 120, when the driver 6220 moves to a firedposition, the staple 6290 can be removed and/or ejected from thefastener cavity 6254. Further, the tissue thickness compensator 6258 andthe tissue T can be clamped between the anvil 6210 and the cartridgebody 6250 of the end effector assembly 6200. The staple forming pockets6214 in the anvil 6210 can form the staple 6290 into a B-form, forexample. Further, at least one barb 6296 a, 6296 b, 6298 a, 6298 b ofthe staple 6290 can engage the tissue clamped within the staple 6290,for example. The barb 6296 a, 6296 b, 6298 a, 6298 b can grip and/orhold the tissue T captured within the staple 6290.

Referring now to FIGS. 121-124, a fastener 6390 can be releasably heldby a lock driver 6320 in a fastener cartridge 6350 (FIGS. 123 and 124)for use with an end effector assembly. In various embodiments, thefastener 6390 can include a base 6392 and legs 6394 a, 6394 b extendingfrom the base 6392. The first leg 6394 a can extend from a first end ofthe base 6392, for example, and a second leg 6394 b can extend from asecond end of the base 6392, for example. In certain embodiments, thelock driver 6320 can releasably hold the base 6392 of the fastener 6390.In various embodiments, the lock driver 6320 can include a catch 6340,which can releasably hook and/or hold the base 6392. The catch 6340 canbe flexible, for example, and can flex to release the base 6392 of thefastener 6390, for example. In various embodiments, the lock driver 6320and/or the catch 6340 can be comprised of plastic, such as Ultem, forexample, with either glass filler or no glass filler such that the catch6340 is sufficiently elastically and/or plastically deformed.

Referring primarily to FIGS. 123 and 124, the lock driver 6320 can bemoveably positioned in a fastener cavity 6354 defined in the cartridgedeck 6352 of the cartridge body 6350. The lock driver 6320 can move froma locked position (FIG. 123) to an unlocked position (FIG. 124) in thefastener cavity. A sled and/or driver in the cartridge body 6350 canengage the lock driver 6320 during a firing stroke to the move the lockdriver 6320 from the locked position to the unlocked position. Invarious embodiments, the fastener 6390 can be secured to the lock driver6320 when the lock driver 6320 is in the locked position, and can bereleased from the lock driver 6320 when the lock driver 6320 is moved tothe unlocked position. When the lock driver 6320 moves from the lockedposition to the unlocked position, the fastener 6390 can be ejected fromthe fastener cavity 6354. A key 6353 adjacent to the fastener cavity6354 can release the fastener 6390 from the lock driver 6320, forexample. The key 6353 can be a lip extending inwardly from at least aportion of the rim of the fastener cavity 6354, for example. In variousembodiments, the key 6353 can have a camming surface 6355. When the lockdriver 6320 moves from the locked position to the unlocked position, aledge 6344 of the catch 6340 can abut the camming surface 6355 of thekey 6353. In such embodiments, as the catch 6340 moves against thecamming surface 6355, the camming surface 6355 can flex the catch 6340,such that the hook 6342 releases the base 6392 of the fastener 6390. Invarious embodiments, the hook 6342 can rotate upwardly to release thebase 6392. For example, the hook 6342 can rotate upwardly such that theopening of the hook 6342 is directed upward toward the tissue thicknesscompensator 6358, and such that the base 6392 can move upward throughthe opening and away from the lock driver 6320.

Referring still to FIGS. 123 and 124, a tissue thickness compensator6358 can be releasably secured to the cartridge deck 6352 of thecartridge body 6350. When the lock driver 6320 is in the locked position(FIG. 123), the staple legs 6394 a, 6394 b can extend from the fastenercavity 6354 into the tissue thickness compensator 6358. The staple legs6394 a, 6394 b can hold the tissue thickness compensator 6358 relativeto the cartridge deck 6352, for example, and can prevent and/or limitlateral movement of the tissue thickness compensator 6358 relative tothe cartridge deck 6352, for example. Further, when the lock driver 6320moves to the unlocked position and the fastener 6390 is ejected from thefastener cavity 6354 (FIG. 124), the catch 6340 can release the base6392 of the fastener 6390 such that the fastener 6390 can disengage thelock drivers 6320 and the cartridge body 6350. When the fasteners 6390removably positioned in the fastener cavities 6354 are ejected fromtheir respective fastener cavities 6354 and disengage the cartridge body6350, the tissue thickness compensator 6858 can be unsecured to and/orreleased from the cartridge body 6350.

Referring now to FIGS. 125-129, an end effector assembly 6400 caninclude a first jaw and/or anvil 6410 (FIGS. 127-129) and a second jaw6402. The second jaw 6402 can include a fastener cartridge body 6450 anda tissue thickness compensator 6458 releasably secured to the second jaw6402 and/or to the tissue thickness compensator 6458. In certainembodiments, the fastener cartridge body 6450 and the tissue thicknesscompensator releasably secured thereto can comprise a fastener cartridgeassembly, for example. In various embodiments, the cartridge body 6450can include a cartridge deck 6452 and a slot 6456 extending through atleast a portion of the cartridge body 6450. Cavities can be defined inthe cartridge deck 6452 and into the cartridge body 6450. For example,fastener cavities 6454 can be defined in the cartridge deck 6452 and canreceive fasteners 6490 (FIGS. 126A-129) therein. The fasteners 6490 canbe removably positioned in the fastener cavities 6454. For example, asingle fastener 6490 can be removably positioned in each fastener cavity6454, and can be ejected from the fastener cavity 6454 during a firingstroke. Further, lock cavities 6448 can be defined in the cartridge deck6452 and can receive locks 6440 therein. For example, a single lock 6440can be moveably positioned in each lock cavity 6448, and can be movedfrom a locked position (FIGS. 127 and 128) to an unlocked position (FIG.129) during the firing stroke.

Referring primarily to FIG. 126, the lock 6440 can include a base 6444and a hook 6442 moveably positioned relative to the base 6444. Forexample, the hook 6442 can move within an aperture formed through atleast a portion of the base 6444. The hook 6442 can receive and/or holda connector 6480, for example. The hook 6442 can be comprised of liquidcrystal polymer (LCP), Nylon, Ultem, polycarbonate, and/or ABS, forexample. The connector 6480 can be a suture, for example. In certainembodiments, the connector can be comprised of PDS, PGA/PCL, PLLA/PCL,TMC/PCL, PGA and/or PCL, for example. In various embodiments, when thehook 6442 is embedded or partially embedded in the base 6444, the hook6442 can constrain the connector 6480. The connector 6480 can be heldbetween the hook 6442 and the base 6444, for example. When the hook 6442is lifted or partially lifted out of the base 6444, the connector 6480can be unconstrained by the hook 6442, for example, and can move out ofengagement with the lock 6440, for example. In various embodiments, theconnector 6480 can slide out of engagement with the lock 6440 when thehook 6442 is at least partially lifted out of the base 6444.

Referring primarily to FIG. 126A, the connector 6480 can extend from thetissue thickness compensator 6458. The tissue thickness compensator 6458can be friction fit and/or thermoformed with the connector 6480, forexample. In various embodiments, the connector 6480 can be threadedthrough the hook 6442 of the lock 6440 when the lock 6440 is in theunlocked position. As the connector 6480 is thread through the hook6442, the tissue thickness compensator 6458 can move into positionrelative to the cartridge body 6450. For example, the tissue thicknesscompensator 6458 can be positioned on the cartridge deck 6452 of thecartridge body 6450. Referring primarily to FIG. 127, once the tissuethickness compensator 6458 is positioned relative to the cartridge body6450, the lock 6440 can be moved from the unlocked position to a lockedposition. For example, the hook 6442 of the lock 6440 can be embedded orpartially embedded in the base 6444 such that the lock 6440 enclosesand/or constrains the connector 6480. In various embodiments, the lock6440 and/or driver 6420 can include a spring, which can bias the lock6440 into the unlocked position, for example. When in the lockedposition, the tissue thickness compensator 6458 can be secured to thecartridge body 6450 by the connector-lock engagement, for example.

Referring primarily to FIGS. 128 and 129, a key can move along at leasta portion of the cartridge body 6450 during a firing stroke. The key canbe a sled 6434 and/or an element of the firing assembly, for example. Invarious embodiments, the sled 6434 can engage the drivers in thecavities in the cartridge body 6450 during the firing stroke. The sled6434 can push the drivers toward the cartridge deck 6452 and/or towardthe tissue thickness compensator 6458 to eject fasteners from thefastener cavities 6454 and/or to move the locks 6440 from the lockedposition to the unlocked position. Referring primarily to FIG. 128, thesled 6434 can engage a driver 6420 in the lock cavity 6448 during thefiring stroke. The sled 6434 can move the driver 6420 toward thecartridge deck 6452 and/or toward the tissue thickness compensator 6458.Further, referring primarily to FIG. 129, the driver 6420 can move thelock 6440 from the locked position to the unlocked position. Forexample, the driver 6420 can push the hook 6442 out of the base 6444.When the hook 6442 is lifted out of the base 6444, the connector can beunconstrained by the lock 6440. In such embodiments, the tissuethickness compensator 6458 can be unsecured to and/or released from thecartridge body 6450, for example.

Referring now to FIG. 67, a tissue thickness compensator 17050, forexample, can comprise a first portion 17052 and a second portion 17054extending relative to the first portion 17052. The tissue thicknesscompensator 17050 can comprise part of a staple cartridge assembly. Insome circumstances, the tissue thickness compensator 17050 can beattached to a cartridge body of the staple cartridge assembly. Incertain circumstances, the tissue thickness compensator can be assembledto an anvil of a surgical stapling instrument. In either event, thefirst portion 17052 of the tissue thickness compensator 17050 can becompressible. In use, the first portion 17052 can be captured withinstaples ejected from the staple cartridge and can apply a compressiveforce to the tissue also captured within the staples. The second portion17054 of the tissue thickness compensator 17050 can extend through thefirst portion 17052 wherein the second portion 17054 can comprise aproximal end 17053 and a distal end 17055 extending from the firstportion 17052. As discussed in greater detail below, the second portion17054 may be less flexible and/or more rigid than the first portion17052. Referring now to FIG. 68, a staple cartridge assembly 17000 cancomprise a cartridge body 17010 including a plurality of staple cavitiesdefined therein and a plurality of staples at least partially storedwithin the staple cavities. As illustrated in FIG. 68, the tissuethickness compensator 17050 can be mounted to the cartridge body 17010.

The staple cartridge assembly 17000 can comprise a proximal mount 17060configured to releasably hold the proximal end 17053 of the secondportion 17054 to the cartridge body 17010 and a distal mount 17070configured to releasably hold the distal end 17055 to the second portion17054. The proximal mount 17060 can comprise a single component or morethan one component. As illustrated in FIG. 68, the proximal mount 17060can comprise a first mount portion 17060 a and a second mount portion17060 b configured to at least partially capture and hold the secondportion 17054 against the cartridge body 17010. Turning now to FIG. 69,each mount portion 17060 a, 17060 b can comprise a key 17062 which canbe releasably secured within a key slot 17012 defined in the cartridgebody 17010. Each key 17062 and key slot 17012 can be sized andconfigured such that the sidewalls of the key slot 17012 can apply aretention force to the key 17062 which resists the removal of the key17062 from the key slot 17012. In various circumstances, the key 17062can be releasably press-fit and/or snap-fit within the key slot 17012.In at least one circumstance, the key 17062 can comprise an enlarged end17063 which can be releasably clamped between the sidewalls of the keyslot 17012, for example. As illustrated in FIGS. 68 and 69, each mountportion 17060 a, 17060 b can comprise a window 17064 configured to atleast partially receive the proximal end 17053 of the second portion17054. In such circumstances, the sidewalls of the window 17064 can beconfigured to engage and compress the tissue thickness compensator 17030against the deck 17014 of the cartridge body 17010. Furthermore, atleast a portion of the second portion 17054 can be contained within themount portions 17060 a, 17060 b.

Referring again to FIGS. 68 and 69, similar to the above, the distalmount 17070 can comprise a window 17074 which can be sized andconfigured to receive at least a portion of the distal end 17055 of thesecond portion 17054. Also similar to the above, the sidewalls of thewindow 17074 can be configured to engage and compress the tissuethickness compensator 17030 against the deck 17014 of the cartridge body17010. Furthermore, at least a portion of the second portion 17054 canbe contained within the mount portion 17070. The distal mount portion17070 can comprise one or more pins 17072 extending therefrom which canbe releasably secured within one or more pin apertures 17011 defined inthe cartridge body 17010. Each pin 17070 and pin aperture 17011 can besized and configured such that the sidewalls of the pin aperture 17011can apply a retention force to the pin 17072 which resists the removalof the pin 17072 from the pin aperture 17011. In various circumstances,each pin 17072 can be releasably press-fit and/or snap-fit within a pinaperture 17011.

To assemble the staple cartridge 17000, in at least one circumstance,the tissue thickness compensator 17030 can be positioned against thedeck 17014 of the cartridge body 17010 and the proximal mounts 17060 andthe distal mount 17070 can then be assembled to cartridge body 17010.The mounts 17060, 17070 can be assembled to the cartridge body 17010 tocapture or trap the tissue thickness compensator 17050 against thecartridge body 17010 as discussed above. As also discussed above, themounts 17060, 17070 can be configured to capture and releasably retainthe ends of the second portion 17074 to the cartridge body 17010. Incertain circumstances, the proximal mounts 17060 and/or the distal mount17070 can be configured to capture at least a portion of the firstportion 17052 therein. While the tissue thickness compensator 17050depicted in FIGS. 67-69 comprises two portions, various alternatives areenvisioned in which a tissue thickness compensator can comprise morethan two portions. For example, a tissue thickness compensator cancomprise a compressible first portion 17052 and two or more rigid secondportions 17054 extending therethrough. Also, for example, a tissuethickness compensator can comprise two or more compressible portionsarranged in any suitable arrangement, such as in two or more layers, forexample.

Once assembled, the staple cartridge 17000 can be assembled to asurgical stapler. In at least one circumstance, the staple cartridge17000 can be removably retained with a channel defined in an endeffector of the surgical stapler and then inserted into a surgical sitewithin a patient. The proximal mounts 17060 and/or the distal mount17070 can be configured to retain the tissue thickness compensator 17050to the cartridge body 17010 while the staple cartridge 17000 is insertedinto and/or manipulated within the surgical site. The second portion17054 of the tissue thickness compensator 17050 can provide sufficientrigidity to the tissue thickness compensator 17050 such that the tissuethickness compensator 17050 does not become detached from the cartridgebody 17010 until one or more of the proximal mounts 17060 and/or thedistal mount 17070 is incised and/or detached from the cartridge body17010, as discussed in greater detail below. Owing to the rigidity ofthe second portion 17054, in various circumstances, the attributes ofthe first portion 17052 of the tissue thickness compensator 17050 can beprimarily or exclusively selected so as to provide the desired tissuecompensation properties of the tissue thickness compensator 17050. Inuse, the second portion 17054 of the tissue thickness compensator 17050can resist relative movement between the proximal end 17053 and thedistal end 17055 and, in various circumstances, resist the movement ofthe proximal end 17053 and the distal end 17055 toward one another.

Once the staple cartridge 17000 has been suitably positioned, in variouscircumstances, a firing member 17030 can be advanced through the staplecartridge 17000 to deploy the staples removably positioned therein. Thestaple cartridge 17000 can include a movable member 17034 which can beadvanced from a proximal end of the staple cartridge 17000 toward adistal end of the staple cartridge 17000 by the firing member 17030. Themovable member 17034, further to the above, can be configured to liftthe staples removably stored within the cartridge body 17010 between anunfired position and a fired position. The firing member 17030 canfurther comprise a cutting portion, such as knife 17032, for example,which can be configured to transect the tissue being stapled as thefiring member 17030 is advanced distally through the staple cartridge17000. The knife 17032 can also be configured to transect the tissuethickness compensator 17050 as the firing member 17030 is advanceddistally through the staple cartridge 17000. Referring primarily toFIGS. 67 and 68, the proximal end 17053 of the second portion 17054 canbe severed by the knife 17032. In at least one such embodiment, thetissue thickness compensator 17050 can be at least partially severed, orentirely severed, along a longitudinal axis at least partially definedby notch 17057 defined therein. As illustrated in FIG. 68, the notch17057 can be aligned, or at least substantially aligned, with alongitudinal knife slot 17015 extending through the cartridge body17010. Once the proximal end 17053 of the second portion 17054 has beenat least partially transected by the knife 17032, the second portion17054 can be at least partially released from, or can be releasablefrom, the proximal mounts 17060 a, 17060 b. In such circumstances, thetissue thickness compensator 17050 can become detached from thecartridge body 17010. For instance, the firing member 17030 may be atleast partially advanced, or entirely advanced, through the staplecartridge 17000 to at least partially, or entirely, implant the tissuethickness compensator 17050 against the tissue and, owing to the atleast partial transection of the tissue thickness compensator 17050,especially the second portion 17054, the tissue thickness compensator17050 can be sufficiently flexible so as to slide out of the proximalmount portions 17060 a, 17060 b and the distal mount 17070. In use, invarious circumstances, the firing member 17030 can be retracted to itsproximal, or starting, position after the firing member 17030 has beenat least partially fired and the tissue thickness compensator 17050 hasbeen at least partially implanted wherein the cartridge body 17010 canthen be pulled away from the implanted tissue thickness compensator17050. For instance, if the cartridge body 17010 is pulled away from thetissue thickness compensator 17050 along the longitudinal axis, the atleast partially transected tissue thickness compensator 17050 may beable to buckle longitudinally and the proximal and distal ends of thetissue thickness compensator 17050 may move toward one another, forexample.

Referring now to FIGS. 70-72, a tissue thickness compensator 17150 cancomprise a compressible portion 17152 and a mount portion 17154extending through and/or extending from the compressible portion 17152.The compressible portion 17152 can comprise a proximal end 17153 whichcan include a thickness which is less than the thickness of the bodyportion 17156 of the tissue thickness compensator 17150. In at least onesuch embodiment, the proximal end 17153 can comprise a tapered portion,for example. Referring again to FIGS. 70-72, a staple cartridgeassembly, such as staple cartridge 17100, for example, can include aproximal mount 17160 configured to releasably secure the mount portion17154 of the tissue thickness compensator 17150 to a cartridge body17010. Proximal mount 17160 can comprise one or more locks 17162extending therefrom which can be received within one or more keyholes10112 defined in the cartridge body 17110. In at least one suchembodiment, each of the locks 17162 can comprise a leg and a footextending from the leg wherein the leg can be configured to flexlaterally as the lock 17162 is inserted into a keyhole 17112 and thenresiliently return, or at least substantially return, to its unflexedconfiguration such that the foot can releasably engage, or move behind,a sidewall of the keyhole 17112. Similar to the above, the proximalmount 17160 can further comprise a cavity 17164 configured to receivethe proximal mount portion 17154 of the tissue thickness compensator17150. The cavity 17164 can be configured to compress the proximal mountportion 17154 against the deck of the cartridge body 17110 and hold theproximal end of the tissue thickness compensator 17150 in position. Invarious circumstances, a firing member, such as firing member 17030, forexample, can be configured to incise the proximal mount 17160 as thefiring member 17030 is being advanced to incise the tissue thicknesscompensator 17150. In at least one such circumstance, the incision ofthe proximal mount 17160 can release the tissue thickness compensator17150 from the cartridge body 17110. Referring again to the embodimentdepicted in FIG. 68, for example, the firing member 17030 can beconfigured to pass through a slot defined between the proximal mountportions 17060 a, 17060 b and, in at least some circumstances, passthrough the proximal mount portions 17060 a, 17060 b without incisingthe same.

Referring now to FIGS. 73-76, further to the above, a proximal mount forreleasably holding a tissue thickness compensator to a cartridge bodycan comprise first and second portions 17260 a, 17260 b which, whenassembled to the cartridge body, can define a longitudinal gap or slot17267 which can be sized and configured to permit the firing member17030 to pass therebetween. Similar to the above, each of the first andsecond portions 17260 a, 17260 b can comprise a cavity 17264 configuredto at least partially receive and hold a tissue thickness compensator inplace. Also similar to the above, each of the first and second portions17260 a, 17260 b can comprise locks 17262 extending therefrom which canbe configured to engage the cartridge body.

As discussed above, a staple cartridge assembly can include a proximalmount or attachment portion configured to hold the proximal end of atissue thickness compensator to the proximal end of a cartridge body anda distal mount or attachment portion configured to hold the distal endof the tissue thickness compensator to the distal end of the cartridgebody. In certain other embodiments, a staple cartridge assembly may onlycomprise at least one proximal mount or at least one distal mount forholding the tissue thickness compensator to the cartridge body. Turningnow to FIG. 147, a cartridge assembly 17300 can comprise a cartridgebody 17310 and a tissue thickness compensator 17350, wherein the distalend of the tissue thickness compensator 17350 can comprise a distal end17355 configured to be releasably mounted to the cartridge body 17310.In at least this embodiment, the distal end of the cartridge body 17310can include lock apertures 17011 configured to receive and attach atleast one distal mount to the cartridge body 17310. The reader willappreciate, at least with respect to this embodiment, that the cartridgeassembly 17300 does not further include a proximal mount for mountingthe proximal end of the tissue thickness compensator 17350 to thecartridge body 17310. In various circumstances, the distal end 17355 canbe integrally formed with the body portion 17356 of the tissue thicknesscompensator 17350 or, alternatively, attached to the body portion 17356.

In various embodiments, referring now to FIGS. 156 and 157, a staplecartridge assembly, such as staple cartridge 10400, for example, cancomprise a cartridge body 10410 including a distal end, or nose, 10419which can be configured to releasably hold a tissue thicknesscompensator 10450 in position. Similar to the above, the tissuethickness compensator 10450 can comprise a first portion 10452 mountedto a second portion 10454, wherein the second portion 10454 can includea distal end 10455 configured to be releasably held by the nose 10419.In various circumstances, the nose 10419 and a deck 10414 of thecartridge body 10410 can define a slot 10418 therebetween configured toreceive the distal end 10455. The nose 10419 can be comprised of aresilient material which can be sized and configured such that the nose10419 is biased into engagement with the distal end 10455. In use,referring to FIG. 157, the nose 10419 can be sufficiently flexible so asto permit the tissue thickness compensator 10450 to slide out fromunderneath the nose 10419 when the cartridge body 10410 is moved awayfrom the tissue thickness compensator 10450 after the tissue thicknesscompensator 10450 has been at least partially implanted. Turning now toFIG. 158, further to the above, the first layer 10452 can be comprisedof a compressible foam which can be mounted to the second layer 10454.In various circumstances, one or more adhesives can be utilized to mountthe first layer 10452 to the second layer 10454. The first layer 10452can be mounted to the second layer 10454 such that the distal end 10455and a notch 10457 defined in the distal end 10455 remain exposed. Thefirst layer 10452 may be mounted to the second layer 10454 such that thefirst layer 10452 is centered laterally with respect to a longitudinalcenter axis 10459 defined by the second layer 10454.

As discussed above, a staple cartridge assembly can include a movablefiring member at least partially stored therein which can be configuredto lift staples stored within the staple cartridge assembly betweenunfired positions and fired positions. Turning now to FIGS. 159 and 160,a staple cartridge assembly 10500 can include a cartridge body 10510, atissue thickness compensator 10550, and a movable firing member, orsled, 10034 slidably stored therein. The sled 10034 can include one ormore ramps 10035 defined thereon which can be configured to lift thestaples from their unfired positions to their fired positions in use.Prior to use, the sled 10034 can be releasably locked in position. In atleast one such embodiment, the tissue thickness compensator 10550 can beconfigured to releasably hold the sled 10034 in a proximal positionbefore the sled 10034 is advanced distally to eject the staples from thestaple cartridge assembly 10500 and incise the tissue thicknesscompensator 10550. The tissue thickness compensator 10550 can compriseone or more tabs, or detents, 10557 extending therefrom which canreleasably engage the sled 10034. For instance, the sled 10034 caninclude one or more recesses 10037 within which the detents 10557 can bepositioned until a sufficient force is applied to the sled 10034 whichcan cause the sled 10034 to overcome the retention force applied to thesled 10034 by the detents 10557. In use, the detents 10557 can beconfigured to hold the sled 10034 in position until a longitudinalfiring force applied to the sled 10034 in the distal direction exceeds athreshold force wherein, when the firing force exceeds the thresholdforce, the sled 10034 can slide distally and the detents 10557 cansufficiently flex, or otherwise deform, to permit the sled 10034 toslide thereby. In at least one embodiment, the detents 10557 can bepositioned proximal to the staple cavities defined in the cartridge body10510 and/or proximal to the staples stored within the cartridge body10510 such that the sled 10034 can be releasably held in an unfiredposition which is proximal to the staples. Once the sled 10034 has beenadvanced distally, the sled 10034 can be advanced toward the staples.

Further to the above, referring again to FIGS. 159 and 160, thecartridge body 10510 can include one or more retention slots 10517 whichcan be configured to receive at least a portion of the detents 10557.More particularly, in at least the illustrated embodiment, a retentionslot 10517 defined in one side of the cartridge body 10510 can bealigned with a recess 10037 defined in a corresponding side of the sled10034 when the sled 10034 is in its proximal, unfired position such thata detent 10557 can be concurrently positioned within the alignedretention slot 10517 and the recess 10037. In at least one suchembodiment, the sidewalls of the retention slot 10517 defined in thecartridge body 10510 can support the detent 10557 and at least inhibitthe detent 10557 from becoming prematurely dislodged from the recess10037. As discussed above, the sled 10034 can be advanced distally suchthat the recess 10037 is no longer aligned with the detent 10557;however, in at least the illustrated embodiment, the detent 10557 mayremain aligned with and/or positioned within the retention slot 10517after the sled 10034 has been at least partially advanced. Referringprimarily to FIG. 159, a first arrangement comprising a detent 10557, asled recess 10037, and a cartridge retention slot 10517 can be arrangedwith respect to a first side of the sled 10034 and a second arrangementcomprising a second detent 10557, a second sled recess 10037, and asecond cartridge retention slot 10517 can be arranged with respect to asecond, or opposite, side of the sled 10034.

Certain embodiments of staple cartridges can include a pliable layer,such as a tissue thickness compensator and/or a buttress material, forexample, on a staple deck, wherein staples can arranged so that the tipsof the unfired staples extend into the layer. In certain otherembodiments, the pliable layer can comprise a compressible and/orcrushable staple cartridge that is implantable in a patient and deformsand/or compresses when captured in the staples. The pliable layer and/orimplantable staple cartridge can also deform and/or compress if asurgeon, nurse, technician, or other user (“user” or “users”)inadvertently presses a thumb or other finger against the pliable layeror implantable staple cartridge, for example. Such deformation and/orcompression can render the staple cartridge unusable.

Staple cartridge retainers are often supplied with retainers, which canassist the user in loading the staple cartridge into a surgical stapler.The retainer can also cover the staple deck and any pliable layer,thereby preventing the users from inadvertently compressing, crushing,and/or deforming the pliable layer. However, users sometimes prematurelyremove the staple cartridge retainer prior to fully installing thestaple cartridge into an end effector of a surgical stapler. Byprematurely removing the retainer, the users can risk causing damage tothe pliable layer.

FIGS. 164-167 illustrate an embodiment of a retainer 10000 that can beattached to a staple cartridge 10010. Referring to FIGS. 166 and 167,the staple cartridge 10010 can include a pliable layer 10020, such as atissue thickness compensator and/or a buttress material, arranged on astaple deck 10011 of the staple cartridge 10010. As shown in FIG. 167,staples 10030 can extend from the staple cartridge 10010 into theexposed pliable layer 10020. If the retainer 10000 is prematurelyremoved, a user may inadvertently press on the pliable layer 10020 whilepushing the staple cartridge 10010 into a staple cartridge channel of anend effector, thereby compressing and/or deforming the layer 10020.

FIGS. 168-173 illustrate an embodiment of a retainer 2600 that can belocked to a staple cartridge 2650 and that cannot be unlocked andremoved from the staple cartridge 2650 until the staple cartridge 2650is fully inserted into a staple cartridge channel 2670 of an endeffector. As best illustrated in FIG. 168, a proximal end portion 2604of the retainer 2600 can include movable cam portions 2616 with lockingtabs 2626 extending from the movable cam portions 2616. The locking tabs2626 extend into and engage a slot 2652, such as a knife slot, in thestaple cartridge 2650. The engagement of the locking tabs 2626 withinthe slot 2652 releasably holds the retainer 2600 and the staplecartridge 2650 together. As explained in greater detail below, thelocking tabs only disengage from the slot 2652 such that the retainer2600 can be released and removed from the staple cartridge 2650 afterthe cam portions 2616 of the retainer 2616 engage a key in the staplecartridge channel 2670 that causes the cam portions 2616 to inwardlyflex toward one another. Furthermore, in various embodiments, the camportions 2616 can only engage the key if the staple cartridge 2650 isproperly seated in the staple cartridge channel 2670.

As described above, in certain embodiments, the proximal end portion2604 of the retainer 2600 can include cam portions 2616, each of whichis attached to the body 2606 of the retainer 2600 by a neck 2624. Thecam portions 2616 can be separated from one another by a gap 2622. Thecam portions 2616 can flex inwardly in the direction of arrow I (shownin FIG. 172) when an inwardly-compressive force is applied and canresiliently flex outwardly in the direction of arrow O (shown in FIG.170) about the necks 2624. A locking tab 2626 can extend from each camportion 2618. As described in greater detail below, when arranged on astaple cartridge 2650, the locking tabs 2626 can extend into andreleasably engage a slot 2652, such as a knife slot, in the staplecartridge 2650. Referring primarily to FIGS. 170 and 171, the camportions can be biased in an outwardly flexed position such that lips2628 extending from the locking tabs 2626 can engage ridges 2654 in theslot 2652 in the staple cartridge 2650. Biasing the cam portions 2616 inthe outwardly flexed position can push the lips 2628 of the locking tabs2626 into engagement with the ridges 2654 in the slot 2652 such that theretainer 2600 is locked to the staple cartridge 2650 absent aninwardly-compressive force from the key of the staple cartridge channel2670.

Referring primarily to FIGS. 170-173, in various embodiments, the key ofthe staple cartridge channel 2670 can include interior walls of thestaple cartridge channel 2670 that provide a progressively increasinginwardly-compressive force to the cam portions 2616 such that the camportions 2616 can flex inwardly in the direction of arrow I (shown inFIG. 172) as the retainer 2600 and the staple cartridge 2650 areinserted into the staple cartridge channel 2670. For example, the staplecartridge channel 2670 can include first interior walls 2672 defining afirst width that can accommodate the cam portions 2616 in their biased,outwardly-flexed position. The staple cartridge channel 2670 can includesecond interior walls 2676 defining a second width that can accommodatethe cam portions 2616 in an inwardly-flexed position, as shown in FIG.172. The staple cartridge channel 2670 can include intermediate interiorwalls 2674 positioned intermediate the first interior walls 2672 and thesecond interior walls 2676 that can transition from the first width tothe second width. In use, the staple cartridge 2650 and the retainer2600 are moved in a proximal direction relative to and toward the staplecartridge channel 2670 to be inserted into the staple cartridge channel2670, indicated by arrow P in FIGS. 170 and 172. Referring primarily toFIGS. 170 and 171, as the staple cartridge 2650 and retainer 2600 aremoved toward the staple cartridge channel 2670, rounded ends 2620 andoutward-facing surfaces 2618 of the cam portions 2616 can engage thefirst walls 2672 of the staple cartridge channel 2670. As describedabove, in certain embodiments, the first walls 2672 can define a widththat accommodates the cam portions 2616 in their biased,outwardly-flexed position. In various other embodiments, the first walls2672 can define a width that accommodates the cam portions 2616 in apartially inwardly-flexed position, wherein the partial amount of inwardflexing is sufficiently enough such that the lips 2628 of the lockingtabs 2626 do not disengage from the ridges 2654 of the staple cartridge2650 and the retainer 2600 becomes unlocked from the staple cartridge2650. Referring now to FIGS. 172 and 173, as the staple cartridge 2650and retainer 2600 continue to move proximally toward the staplecartridge channel 2670 in the direction of arrow P, the rounded ends2620 and outward-facing surfaces 2618 engage the intermediate walls 2674and then the second walls 2676. The intermediate walls 2674 and thesecond walls 2676 can provide a progressively increasing force that cancause the cam portions 2616 to flex progressively inward. Eventually,the cam portions 2616 will flex inwardly by an amount such that the lips2628 of the locking tabs 2626 can be disengaged from the ridges 2654 inthe slot 2652 of the staple cartridge 2650. When the locking tabs 2626are disengaged from the ridges 2654, the retainer 2600 is unlocked fromthe staple cartridge 2650 such that the retainer 2600 can be removedfrom the staple cartridge 2650. In various embodiments, the cam portions2616 flex inwardly so that the tabs 2626 disengage from the ridges 2654only when the staple cartridge 2650 is fully inserted into the staplecartridge channel 2670.

In certain embodiments, a lockable retainer, such as retainer 2600described above with reference to FIGS. 168-173, can also prevent astaple cartridge of a particular size from being inserted into an endeffector that is intended for use with a staple cartridge of a differentparticular size. For example, the staple cartridge 2650 can comprise adatum surface 2632 that can engage a datum surface 2674 of the staplecartridge channel 2670. A first predetermined distance from the datumsurface 2632 of the staple cartridge 2650 to the cam portions 2616 cancorrespond to a second predetermined distance between the datum surface2674 of the staple cartridge channel 2670 and the walls 2672, 2674, and2676 that comprise the key of the staple cartridge channel 2670. Thefirst and second predetermined distances for a particularly-sizedretainer and staple cartridge and for a staple cartridge channelintended for use with the particularly-sized staple cartridge can bedifferent from the first and second predetermined distances for otherdifferently-sized retainers, staple cartridges, and staple cartridgechannels. Put differently, each size of staple cartridge, retainer, andstaple cartridge channel can have a first predetermined distance and asecond predetermined distance that is different from other sizes ofstaple cartridge, retainer, and staple cartridge channel. As a result,attempting to insert a staple cartridge and retainer into aincorrectly-sized staple cartridge channel can result in the camportions of the retainer not engaging the walls of the staple cartridgechannel and/or the datum surfaces of the staple cartridge and the staplecartridge channel not engaging. For example, the staple cartridge 2650and the retainer 2600 can be arranged so that, when they are insertedinto a correctly-sized staple cartridge channel, the cam portions 2616can only engage the second walls 2676 of the staple cartridge channel2670 such that the locking tabs 2626 disengage from the slot 2652 in thestaple cartridge 2650 when the datum surfaces 2632 and 2674 engage oneanother. If the staple cartridge 2650 and the retainer 2600 are tooshort for the staple cartridge channel 2670, for example, then the camportions 2616 may not reach the second walls 2676 such that the lockingtabs 2626 can be disengaged from the slot 2552 in the staple cartridge2650 when the datum surfaces 2632 and 2674 are engaged. As a result, theretainer 2600 would not be unlocked and removable from the staplecartridge 2650. Conversely, if the staple cartridge 2650 and theretainer 2600 are too long for the staple cartridge channel 2670, forexample, then the cam portions 2616 engaging the second walls 2676 ofthe staple cartridge channel 2670 could prevent the datum surfaces 2632and 2674 of the staple cartridge 2650 and the staple cartridge channel2670, respectively, from engaging. As a result, the staple cartridge2650 would not be completely seated in the staple cartridge channel2670.

In addition to the locking tabs 2626 extending from the cam portions2616, the retainer 2600 can also include a pair of proximal tabs 2612arranged near a proximal end 2602 of the retainer 2600 and a pair ofdistal tabs 2610 arranged near a distal end 2604 of the retainer 2600.The proximal tabs 2608 and the distal tabs 2610 can extend from the body2606 and can engage and releasably hold the staple cartridge 2650. Incertain embodiments, the proximal tabs 2612 and the distal tabs 2610 canengage and hold the staple cartridge 2650 until the staple cartridge2650 is fully seated in the staple cartridge channel 2670. Stateddifferently, the proximal tabs 2612 and/or the distal tabs 2610 canserve as another lock that prevents the retainer 2600 from being removedfrom the staple cartridge 2650 before the staple cartridge 2650 iscompletely seated in the staple cartridge channel 2670.

Referring primarily to FIG. 168, each proximal tab 2612 can include aproximal lip 2614 and each distal tab 2610 can include a distal lip2610. Each proximal lip 2614 can include an inward-facing angled surface2615 and each distal lip 2610 can include an inward-facing angledsurface 2611. The proximal lips 2614 and the distal lips 2610 can engageand releasably hold lateral sides of the staple cartridge 2650. When thestaple cartridge 2650 and the retainer 2600 are inserted into the staplecartridge channel 2670, the inward-facing angled surfaces 2611 and 2615can engage edges 2672 and 2678 of the staple cartridge channel 2670. Theedges 2672 and 2678 of the staple cartridge channel 2670 can flexoutwardly the proximal tabs 2612 and/or the distal tabs 2610 such thatthe proximal lips 2614 and the distal lips 2610 disengage from thelateral sides of the staple cartridge 2650. When the proximal lips 2614and the distal lips 2610 are disengaged, the retainer 2600 can bereleased and removed from the staple cartridge 2650.

Referring to FIGS. 174-180, the end effector 12 of a surgicalinstrument, for example, can be configured to receive an end effectorinsert 28010. In various embodiments, the end effector insert 28010 cancomprise a compensator body 28012 and at least one clip 28014 a, 28014b. In various embodiments, the end effector insert 28010 can comprise aproximal clip 28014 b at the proximal end of the compensator body 28012and a distal clip 28014 a at the distal end of the compensator body28012, for example. Referring primarily to FIG. 177, the distal clip28014 a can be secured to the anvil 25060 of the end effector 12 at ornear the distal end of the anvil 25060. For example, the distal clip28014 a can be substantially aligned with and/or partially positionedwithin the longitudinal slot 25062 of the anvil 25060. Referringprimarily to FIG. 178, the proximal clip 28014 b can be secured to astaple cartridge 25000 in the lower jaw 25070 of the end effector 12(FIG. 179). The proximal clip 28014 b can be secured to the staplecartridge 25000 at or near the proximal end of the staple cartridge25000. For example, the proximal clip 28014 b can be substantiallyaligned with and/or positioned within a longitudinal slot 25004 in thestaple cartridge 25000.

Referring now to FIGS. 179 and 180, the end effector insert 28010 can beinserted into the end effector 12 of a surgical instrument. In variousembodiments, at least a portion of the end effector insert 28010, suchas the compensator body 28012, distal clips 28014 a, and/or proximalclip 28014 b, can be deformable and/or resilient, for example. When theend effector insert 28010 is inserted into the end effector 12, thedistal and/or the proximal clips 28014 a, 28014 b can bend or flex. Whenthe clips 28014 a, 28014 b are flexed, for example, the clips 28014 a,28014 b can seek to return to their initial, undeformed configurationand can generate a corresponding springback or restoring force, forexample. In various embodiments, when the end effector insert 28010 ispositioned within the end effector 12, the end effector insert 28010 canapply a spring load to the end effector 12. In some embodiments, the endeffector insert 28010 can be solid or substantially solid such that anoperator can grasp the insert 28010 when the operator is inserting theend effector insert 28010 and staple cartridge 25000 into the endeffector 12.

In some embodiments, the end effector insert 28010 can be removed fromthe end effector 12 prior to cutting and/or fastening operations of theend effector 12. In other embodiments, the end effector insert 28010 canremain positioned in the end effector 12 during cutting and/or firingoperations. For example, the end effector insert 28010 can be transectedby the cutting element 25052 as staples are fired from their staplescavities 25002 (FIG. 178) in the staple cartridge 25000. In variousembodiments, the end effector insert 28010 can comprise a tissuethickness compensation material, similar to at least one of the tissuethickness compensators described herein. For example, the end effectorinsert 28010 can comprise a polymeric composition, such as abioabsorbable, biocompatible elastomeric polymer, for example. The endeffector insert 28010 can further comprise a bioabsorbable polymer, suchas, for example, lyophilized polysaccharide, glycoprotein, elastin,proteoglycan, gelatin, collagen, and/or oxidized regenerated cellulose(ORC), for example. In some embodiments, the end effector insert 28010can comprise at least one therapeutic agent such as a pharmaceuticallyactive agent or medicament.

Referring still to FIGS. 174-180, the end effector insert 28010 can bereleasably attached to the end effector 12 and/or to the anvil 25060and/or the staple cartridge 25000 of the end effector 12. The proximalclip 28014 b can be releasably secured to the staple cartridge 25000(FIG. 178), for example, and the distal clip 28014 a can be releasablysecured to the anvil 25060 (FIG. 177), for example. In variousembodiments, the proximal clip 28014 b can be aligned with and/orretained within the slot 25004 of the staple cartridge 25000. Further,in certain embodiments, the distal clip 28014 a can be aligned withand/or retained within the slot 25062 of the anvil 25060. Referringprimarily to FIG. 179, in certain embodiments, the proximal clip 28014 bcan be releasably secured to the staple cartridge 25000 before thestaple cartridge 25000 is positioned in the lower jaw 25070 (FIG. 179).As the staple cartridge 25000 and the attached end effector insert 28010are moved toward and/or into the end effector 12 and/or the lower jaw25070, the distal clip 28014 a can be moved into alignment with the slot25062 in the anvil 25060, for example. In various embodiments, when thestaple cartridge 25000 and the end effector insert 28010 are positionedin the end effector 12 (FIG. 180), the distal clip 28014 a canreleasably engage the anvil 25060. The distal clip 28014 a can slideinto the slot 25062 in the anvil 25060, for example. In variousembodiments, the distal clip 28014 a can be positioned relative to theanvil 25060 before or while the proximal clip 28014 b is positionedrelative to the staple cartridge 25000.

When the end effector insert 28010 is releasably secured within the endeffector 12, for example by the proximal clip 28014 b and the distalclip 28014 a as described herein, the end effector insert 28010 can beheld in tension in the end effector 12. Stated differently, the proximalclip 28014 b secured relative to the staple cartridge 25000 in the lowerjaw 25070 can exert a pulling force along the end effector insert 28010and on the distal clip 28014 a secured relative to the anvil 25060, forexample. In various embodiments, the tension between the proximal clip28015 b and the distal clip 28014 a can help to hold the end effectorinsert 28010 in the end effector 12.

In various embodiments, when the staple cartridge 25000 and end effectorinsert 28010 are positioned in the end effector 12, the proximal clip28014 b can be positioned intermediate the unfired sled 25056 (FIG. 178)and the staple cartridge 25000. For example, the unfired sled 25056 canbe proximal to the proximal clip 28013 b. In certain embodiments, duringa firing stroke, the sled 25056 can move distally past the proximal clip28014 b, and can deflect the proximal clip 28014 b, for example. Invarious embodiments, when the sled 25056 deflects the proximal clip28014 b during the firing stroke, the proximal clip 28014 b can bereleased from the slot 25004 in the staple cartridge 25000. In certainembodiments, the sled 25056 and/or an element of the firing bar 25050(illustrated elsewhere) can release the proximal clip 28014 b from thestaple cartridge 25000. Further, when the proximal clip 28014 b isreleased from the staple cartridge 25000, the tension in the endeffector insert 28010 can be at least partially relieved. In the absenceof a pulling force exerted on the distal clip 28014 a, the distal clip28014 a can release from the anvil 25060. Accordingly, the end effectorinsert 28010 can be released from the end effector 12 and, for example,can remain in the patient's tissue after the end effector 12 has beenremoved from the patient.

In certain embodiments, a proximal end of an anvil-attachable layer,such as a tissue thickness compensator and/or a buttress material, forexample, can be releasably attached to a proximal end of a staplecartridge for alignment with and attachment to an anvil of an endeffector into which the staple cartridge can be inserted. Generally, theanvil-attachable layer can be arranged relative to an anvil-facing sideof a staple cartridge. For example, the anvil-attachable layer can bearranged on a staple deck of the staple cartridge and/or can be arrangedon a staple deck layer. A proximal end of the anvil-attachable layer canbe attached to a proximal end of the staple cartridge or a proximal endof the staple deck layer. After the staple cartridge is inserted intothe end effector of the surgical stapler, the anvil of the surgicalstapler can be closed against the anvil-attachable layer such that thelayer becomes attached to the anvil. When the anvil is reopened, theanvil-attachable layer, now attached to the anvil, can move with theanvil and away from the staple cartridge. In various circumstances, asthe attached layer moves with the anvil, the attached layer can pivotabout its proximal end that is attached to the staple cartridge and/orthe staple cartridge layer. In various other circumstances, as theattached layer moves with the anvil, the proximal end of the layer candetach from the staple cartridge. The surgical stapler, with theanvil-attachable layer attached to the anvil, can now cut and staplepatient tissue. The anvil-attachable layer can also be cut by thesurgical stapler and captured by the staples. After the anvil-attachablelayer and patient tissue are captured by the staples, the surgicalstapler can be removed from the patient. In various embodiments in whichthe anvil-attachable layer is still attached to the staple cartridge,the surgical stapler can be pulled free from the layer, breaking theattachment between the layer and the staple cartridge.

FIGS. 181 and 182 illustrate an embodiment of a staple cartridgeassembly 2400 comprising an anvil-attachable layer 2414. Theanvil-attachable layer 2414 can comprise a tissue thickness compensatorand/or a buttress material, for example. A proximal end 2416 of theanvil-attachable layer 2414 can be attached to a proximal end 2418 of astaple cartridge body 2402. In various embodiments, the staple cartridgeassembly 2400 can include a staple cartridge layer 2412, such as atissue thickness compensator and/or a buttress material, for example,arranged on a staple deck of the staple cartridge body 2402. A cartridgepan 2404 can at least partially surround the staple cartridge body 2402and can be comprised of a metal material, for example. The staplecartridge body 2402 can include a surface 2406 and grooves 2408 definedin the surface 2406 at a proximal end 2418 of the cartridge body 2402.Referring to FIG. 181, in order to attach the anvil-attachable layer2414 to the staple cartridge body 2402, a proximal end portion 2416 ofthe anvil-attachable layer 2414 can be positioned over the grooves 2408.Then, as shown in FIG. 182, tabs 2410 extending from the cartridge pan2404 can be deformed such that they extend into the grooves 2408,capturing the proximal end portion 2416 of the anvil-attachable layer2414 in the grooves 2408 between the side walls of the grooves 2408 andthe tabs 2410, for example. The tabs 2410 can also capture theanvil-attachable layer 2414 between bottoms of the grooves 2408 and thetabs 2410, for example.

In use, the staple cartridge assembly 2400 shown in FIG. 182, can beinserted into a staple cartridge channel of an end effector of asurgical stapler. Then, an anvil of the end effector can be closedagainst the anvil-attachable layer 2414. The anvil-attachable layer 2414can be arranged on the staple cartridge body 2402 such that the layer2414 is properly aligned with the anvil when the staple cartridgeassembly 2400 is inserted into the staple cartridge channel 2400 and theanvil is then closed. In various embodiments, an anvil-facing surface2415 of the anvil-attachable layer 2414 can include an adhesive that canadhere to a surface of the anvil and/or one or more attachment featuresthat engage the anvil to attach the anvil-attachable layer 2414 to theanvil. For example, the anvil-facing surface 2415 can include one ormore protrusions extending therefrom that can engage a knife slot of theanvil. After the anvil-attachable layer 2414 has been attached to theanvil, the anvil can be returned to an open position with theanvil-attachable layer 2414 attached thereto. The portion of theanvil-attachable layer 2414 attached to the anvil can pivot about theproximal end 2416 of the layer 2414 that is attached to the staplecartridge body 2402 to enable the layer 2414 to move with the anvil.Now, the surgical stapler can comprise a staple cartridge layer 2412aligned on the staple cartridge body 2402 and the anvil-attachable layer2414 attached to and aligned with the anvil.

When the staple cartridge layer 2412 aligned with the staple cartridgebody 2402 and the anvil-attachable layer 2414 attached to and alignedwith the anvil, the surgical stapler is prepared for use to cut andstaple patient tissue. The staple cartridge body 2402 and the staplecartridge layer 2412 can be positioned on one side of the patient tissueand the anvil and anvil-attachable layer 2414 can be positioned on anopposite side of the patient tissue. The attachment of theanvil-attachable layer 2414 to the anvil and to the staple cartridgebody 2402 can stabilize the anvil-attachable layer 2414 relative to theanvil while the stapler is being positioned against the patient tissue.When the surgical stapler is properly positioned relative to patienttissue, the anvil can be closed, capturing the tissue between the staplecartridge body 2402 and the staple cartridge layer 2412 on one side ofthe tissue and the anvil and the anvil-attachable layer 2414 on a secondopposing side of the tissue.

After the anvil is closed with patient tissue captured between thestaple cartridge body 2402 and the staple cartridge layer 2412 on oneside and the anvil and anvil-attachable layer 2414 on the other side,the surgical stapler can be fired. For example, a staple driver can beadvanced in a distal direction through staple driver slots 2422 in thestaple cartridge body 2402 to fire and form staples that are stored inthe staple cartridge. The fired and formed staples can capture thestaple cartridge layer 2412, the anvil-attachable layer 2414, and thepatient tissue therebetween. Also, a cutting blade can be advanced inthe distal direction through a knife slot 2420 in the cartridge body2402 and a knife slot in the anvil. The cutting blade can sever thestaple cartridge layer 2412, the anvil-attachable layer 2414, and thepatient tissue therebetween as the cutting blade is advanced. In variousembodiments, the staple driver and the cutting blade can be advancedsimultaneously. In various circumstances, the staple driver can lead thecutting blade such that the staples are fired and formed before thecutting blade severs the patient tissue, the staple cartridge layer2412, and the anvil-attachable layer 2414.

After the staple cartridge layer, the anvil-attachable layer 2414, andthe patient tissue therebetween have been captured by the staples andcut by the cutting blade, the anvil can be reopened. When the anvil isreopened, the anvil-attachable layer 2414 that is now attached to thestaple cartridge layer 2412 and the patient tissue by the staples can bedetached from the anvil. For example, as the anvil is opened and/or asthe surgical stapler is removed from the patient, the anvil-attachablelayer 2414 can be held in place by the staples and the patient tissue,such that the layer 2414 can be pulled away from an adhesive and/orattachment feature, for example, that is holding the layer 2414 to theanvil. Furthermore, the proximal end 2416 of the anvil-attachable layer2414 can be pulled away from the staple cartridge body 2402 in order tobe detached from the proximal end 2416 of the staple cartridge body2402. For example, in various circumstances, the portions of theproximal end 2416 of the anvil-attachable layer 2414 captured betweenthe grooves 2408 in the cartridge body 2402 and the tabs 2410 of thecartridge pan 2404 can be pulled out from between the tabs 2410 and thegrooves 2408. In various other circumstances, the anvil-attachable layer2414 can be torn away from portions of the anvil-attachable layer 2414that are captured between the grooves 2408 and the tabs 2410 of thecartridge pan 2404. For example, the portion of the anvil-attachablelayer 2414 captured between the grooves 2408 and the tabs 2410 can bedistressed by the tabs 2410 pressing into the portion of the layer 2414in order to reduce the force required to tear the remaining portion ofthe layer 2414 and/or to define locations where the layer 2414 willtear. For example, the tabs 2410 extending into the anvil-adjustablelayer 2414 may partially score, cut, and/or perforate the layer 2414,for example. After the staple cartridge layer 2412 is detached from thestaple cartridge body 2402 and the anvil-attachable layer 2414 isdetached from the staple cartridge body 2402 and the anvil, the surgicalstapler can be removed from the patient, leaving the layers 2412 and2414 implanted in the patient. The layers 2412 and 2414 can bolster thelines of staples and/or can compress to different thicknesses indifferent staples to provide at least a minimum amount of compression topatient tissue captured by the staples, for example.

Still referring to FIGS. 181 and 182, in various embodiments, the anvilattachable layer 2414 can be detached from the staple cartridge body2402 after the layer 2414 is attached to the anvil and the anvil isreopened. As described above, after the staple cartridge assembly 2400is inserted into a staple cartridge channel and an anvil is closed onthe anvil-attachable layer 2414, the layer 2414 can be attached to ananvil by an adhesive and/or attachment feature on an anvil-facingsurface 2415 of the layer 2414. When the anvil is reopened, theanvil-attachable layer 2414 can move with the anvil away from the staplecartridge body 2402. In various circumstances, movement of the anvil andthe anvil-attachable layer 2414 away from the staple cartridge body 2402can pull the portions of the layer 2414 captured between the tabs 2410of the cartridge pan 2404 and the grooves 2408 in the cartridge body2402 out from between the tabs 2410 and the grooves 2408 such that theproximal end 2416 of the layer 2414 can also move with the anvil.

FIGS. 183 and 184 illustrate another embodiment comprising a staplecartridge assembly 2450 that includes an anvil-attachable layer 2464attachable to a staple cartridge body 2452. In this embodiment, aproximal end 2466 of the anvil-attachable layer 2464 is attached tosurfaces 2472 on attachment portions 2470 that can extend from a surface2456 of the cartridge body 2452. The proximal end 2466 of theanvil-attachable layer 2464 can be attached to the surfaces 2472 byadhesives, ultrasonic welding, thermal welding, and/or heat staking, forexample. In various embodiments, the staple cartridge assembly 2450 caninclude a staple cartridge layer 2462 arranged on the staple cartridgebody 2462. In such embodiments, the attachment portions 2470 can extendfrom the surface 2456 of the cartridge body 2452 such that the surfaces2472 are approximately level with an anvil-facing surface 2467 of thestaple cartridge layer 2462. As a result, the anvil-attachable layer2464 can lie substantially flat across the anvil-facing surface 2467 ofthe staple cartridge layer 2462 and the surfaces 2472. In variouscircumstances, similar to the embodiments described above with respectto FIGS. 181 and 182, after the staple cartridge assembly 2450 isinserted into a staple cartridge channel of an end effector, an anvil ofthe end effector can be closed in order to make contact with ananvil-facing side 2465 of the anvil-attachable layer 2464. An adhesiveand/or attachment features on the anvil-facing side 2465 of theanvil-attachable layer 2464 can attach the anvil-attachable layer 2464to the anvil. Then, when the anvil is reopened, the anvil-attachablelayer 2464 can pivot about the proximal end 2466 attached to thesurfaces 2472. Similar to the embodiments described above with respectto FIGS. 181 and 182, the staple cartridge layer 2462, theanvil-attachable layer 2464, and patient tissue therebetween can be cutand stapled together. Then, the anvil of the surgical stapler isreopened and/or the surgical stapler is removed from the patient, theanvil-attachable layer 2464 can be detached from the anvil and thestaple cartridge layer 2462 can be detached from the staple cartridgebody 2452. Also, the proximal end 2466 of the anvil-attachable layer2464 can detach from the adhesive and/or other attachment to thesurfaces 2472 such that the anvil-attachable layer 2464 can be implantedin the patient.

Still referring to FIGS. 183 and 184, in various embodiments, when theanvil is reopened after the anvil-attachable layer 2464 is attachedthereto, the proximal end 2466 of the anvil-attachable layer 2464 candetach from the surfaces 2472. For example, the proximal end 2466 of theanvil-attachable layer 2464 can also be attached to the anvil. When theanvil and attached anvil-attachable layer 2464 move in a direction awayfrom the staple cartridge body 2452 and/or the staple cartridge layer2462, the proximal end 2466 of the layer 2464 can be pulled and detachfrom the surfaces 2472. In such embodiments, the anvil-attachable layer2464 can be detached from the staple cartridge before the staplecartridge layer 2464, the anvil-attachable layer 2464, and patienttissue therebetween are cut and stapled.

FIGS. 185 and 186 illustrate another embodiment comprising a staplecartridge assembly 2500 that includes a staple cartridge layer 2506 andan anvil-attachable layer 2510. In the embodiment shown in FIGS. 185 and186, the anvil-attachable layer 2510 is attached to the staple cartridgelayer 2506 instead of to the staple cartridge body 2502. The staplecartridge layer 2506 and the anvil-attachable layer 2510 each cancomprise a tissue thickness compensator and/or a buttress material, forexample. The anvil-attachable layer 2510 can include a first proximaltab portion 2512 extending from a proximal end 2508 of the layer 2510.The first proximal tab portion 2512 can be attached to a proximal endsurface 2516 of the staple cartridge layer 2506. For example, the firstproximal tab portion 2512 can be glued, welded, and/or overmolded ontothe proximal end surface 2516 of the staple cartridge layer 2506. Incertain embodiments, the anvil-attachable layer 2510 can include asecond proximal tab portion 2514 extending from the first proximal tabportion 2512. The second proximal tab portion 2514 can be attached to abottom surface 2518 of the staple cartridge layer 2506 by gluing,welding, and/or overmolding, for example.

Similar to the embodiments described above with reference to FIGS.181-184, after the staple cartridge assembly 2500 is inserted into astaple cartridge channel of an end effector of a surgical stapler andwhen an anvil of the end effector is closed on the anvil-attachablelayer 2510, an anvil-facing surface 2511 of the anvil-attachable layer2510 can be attached to the anvil by an adhesive and/or by attachmentfeatures. When the anvil is reopened, the anvil-attachable layer 2510can move away from the staple cartridge layer 2506 and the staplecartridge body 2502 with the anvil. In various circumstances, theanvil-attachable layer 2510 can pivot about the first tab portion 2512as the anvil reopens. After the anvil-attachable layer 2510 is attachedto the anvil, the end effector can be closed on patient tissue such thatthe staple cartridge body 2502 and staple cartridge layer 2506 arepositioned on a first side of the patient tissue and the anvil andanvil-attachable layer 2510 are positioned on a second opposing side ofthe patient tissue. As described above with reference to FIGS. 181 and182, a cutting blade can be advanced through a knife slot 2520 in thecartridge body 2502 and a staple driver can be advanced through a stapledriver slot 2422 in the cartridge body 2502. Referring primarily to FIG.185, in certain embodiments, the first tab portion 2512 and the secondtab portion 2514 of the anvil-attachable layer can by aligned with theknife slot 2512. As the cutting blade is advanced through the knife slot2520, the cutting blade can sever the first tab portion 2512 and thesecond tab portion 2514. In various circumstances, the severing of thefirst tab portion 2512 and the second tab portion 2514 by the cuttingblade can detach the first tab portion 2512 and the second tab portion2514 from the staple cartridge layer 2506. After the cutting blade andthe staple driver have been advanced and the staple cartridge layer2506, the anvil-attachable layer 2510, and patient tissue therebetweenhave been cut and stapled, the anvil may be reopened such that theanvil-attachable layer 2510 separates from the anvil and the staplecartridge layer 2506 separates from the staple cartridge body 2502. Asnoted above, the anvil-attachable layer 2510 in the embodiment of FIGS.185 and 186 is attached to the staple cartridge layer 2506 and not tothe staple cartridge body 2502. Thus, no action is needed to separatethe anvil-attachable layer 2510 from the staple cartridge body 2502.Furthermore, the first tab portion 2512 and/or the second tab portion2514 of the anvil-attachable layer 2510 can remain attached to thestaple cartridge layer 2506 since both layers are captured by staplesand are implantable in the patient. For example, if the cutting bladedoes not detach the first tab portion 2512 and the second tab portion2514 from the staple cartridge layer 2506, then the staple cartridgelayer 2506 and the anvil-attachable layer 2510 will be attached to eachother inside of the patient by the formed staples and by the first andsecond tab portions 2512 and 2514.

Still referring to FIGS. 185 and 186, in various embodiments, after thestaple cartridge assembly 2500 has been inserted in to the staplecartridge channel and the anvil-attachable layer 2510 has been attachedto the anvil, the first tab portion 2512 and the second tab portion 2514can detach from the staple cartridge layer 2506 when the anvil isreopened and the anvil and anvil-attachable layer 2510 move away fromthe staple cartridge layer 2506. For example, the anvil and theanvil-attachable layer 2510 attached thereto can pull the first tabportion 2512 and the second tab portion 2514 away from the staplecartridge layer 2506 such that the first tab portion 2512 and the secondtab portion 2514 detach from the staple cartridge layer 2506.

FIGS. 187 and 188 illustrate another embodiment comprising ananvil-attachable layer 2550 for use with a surgical stapler. Asexplained below, a proximal end portion 2554 of the anvil-attachablelayer 2550 is attachable to a proximal end portion of a staple cartridgefor insertion into an end effector of the surgical stapler and foralignment and attachment to an anvil of the end effector. A body 2552 ofthe anvil-attachable layer 2550 can be detached from the staplecartridge by a cutting blade of the surgical stapler at the beginning ofthe stroke of the cutting blade. For example, the cutting blade 2570shown in FIG. 188 can detach the anvil-attachable layer 2550 from thestaple cartridge before any patient tissue is cut and before any portionof the body 2552 of the anvil-attachable layer 2550 has been captured bystaples.

Referring primarily to FIG. 187, the anvil-attachable layer 2550 caninclude a body 2552 and a proximal end portion 2554. The proximal endportion 2554 includes attachment features 2556 that can attach to aproximal end portion of a staple cartridge. For example, the attachmentfeatures 2556 can include adhesives, welds, and/or heat staking. Theattachment feature 2556 can also comprise a portion captured between aslot in a staple cartridge and a tab of a cartridge pan, as describedabove with respect to FIGS. 181 and 182, for example. Theanvil-attachable layer 2550 can be attached to and aligned with thestaple cartridge such staple cavities of the staple cartridge arealigned with the body 2552 of the layer 2550. Put differently, whenstaples from the staple cartridge have been fired, the staples willcapture the body 2552 of the anvil-attachable layer 2550. Similar to theembodiments described above with reference to FIGS. 181-186, a staplecartridge assembly that includes the anvil-attachable layer 2550attached to a staple cartridge can be inserted into a staple cartridgechannel of an end effector of a surgical stapler. An anvil of the endeffector can close on an anvil-facing surface 2553 of theanvil-attachable layer 2550. The anvil-facing surface 2553 can includean adhesive and/or attachment features that releasably attach theanvil-attachable layer 2550 to the anvil when the anvil is closed on theanvil-facing surface 2553. When the anvil is reopened, theanvil-attachable layer 2550 can pivot about the attachment features 2556to move with the anvil. Similar to the embodiments described above withreference to FIGS. 181-186, the staple cartridge can include a staplecartridge layer, such as a tissue thickness compensator and/or abuttress material, for example.

The anvil-attachable layer 2550 can comprise a first lateral side 2566and a second lateral side 2568. The first lateral side 2566 and thesecond later side 2568 can define a midline 2564 therebetween. Incertain embodiments, the anvil-attachable layer 2550 can be attached toand aligned with the anvil of the end effector such that the midline2564 is aligned with a knife slot in the anvil and a knife slot in thestaple cartridge. The body 2552 of the anvil-attachable layer 2550 caninclude a first lateral slit 2558 positioned near a proximal end andextending from the first lateral side 2566 and past the midline 2564.The body 2552 of the anvil-attachable layer 2550 also can include asecond lateral slit 2560 positioned proximally relative to the firstlateral slit 2558 extending from the second lateral side 2568 and pastthe midline 2564. The first lateral slit 2558 and the second lateralslit 2560 can define a connector portion 2562 therebetween that canconnect the body 2552 of the anvil-attachable layer 2550 to the proximalend portion 2554 of the layer 2550.

Referring primarily to FIG. 188, after the anvil-attachable layer 2550is releasably attached to the anvil of the end effector, the endeffector can be closed on patient tissue such that the anvil and theanvil-attachable layer 2550 are on one side of the tissue and the staplecartridge and/or the staple cartridge layer is on an opposite side ofthe tissue. Then, a cutting blade 2570 can be advanced through a knifeslot in the cartridge, such as knife slot 2418 shown in FIGS. 181-185,for example, and a knife slot in the anvil. The midline 2564 of theanvil-attachable layer 2550 can be aligned with the knife slots suchthat the cutting blade 2570 progressively cuts the anvil-attachablelayer 2550 along the midline. As the cutting blade advances through theanvil-attachable layer 2550 in a distal direction indicated by arrow D,a cutting edge 2572 of the cutting blade 2570 first cuts the proximalend portion 2554 of the layer 2550 before then cutting through theconnector portion 2562, separating the body 2552 of the layer 2550 fromthe proximal end portion 2554 of the layer 2550. Finally, the cuttingblade 2570 cuts through the body 2552 of the anvil-attachable layer2550. After the cutting blade 2570 has advanced through theanvil-attachable layer 2550, the layer is divided in four pieces. Thebody 2552 of the anvil-attachable layer 2550 is detached from theproximal portion 2554 of the layer 2550. Furthermore, the body 2552 ofthe anvil-attachable layer 2550 is divided into two pieces 2580 and 2582and the proximal portion 2554 of the layer 2550 is divided into twopieces 2586 and 2588.

In various circumstances, a surgeon using a surgical stapler may notcompletely fire the stapler. For example, referring to FIG. 188, thesurgeon may only advance the cutting blade 2570 and the staple driverhalfway through the body 2552 of the anvil-attachable layer 2550.Continuing the example, the body 2552 of the anvil-attachable layer 2550is released from the staple cartridge at the beginning of the cuttingstroke of the cutting blade 2570 when the blade 2570 severs theconnector portion 2560 of the layer 2550. The cutting blade 2570 willthen be advanced to cut along the midline 2564 along approximately halfthe length of the body 2552 of the anvil-attachable layer 2550.Likewise, a staple driver can advance to fire and form staples inpatient tissue and in the half of the body 2552 of the layer 2550 thatis cut by the cutting blade 2570. The remaining half of the body 2552 ofthe anvil-attachable layer 2550 is not cut and is not captured bystaples. The cutting blade 2570 and the staple driver can then beretracted and the anvil can be reopened. When the anvil is reopened, theportion of the body 2552 of the anvil-attachable layer 2550 that iscaptured by the staples and attached to patient tissue can detach fromthe anvil. As described above, the connector portion 2560 connecting thebody 2552 of the anvil-attachable layer 2550 to the proximal end portion2554 can be severed before any staples are fired and before the cuttingblade 2570 severs any patient tissue or any portion of the body 2552 ofthe layer 2550. Therefore, the body 2552 of the layer 2550 is alreadyfree from the staple cartridge. When the surgical stapler is removedfrom the patient, the portion of the body 2552 of the anvil-attachablelayer 2550 that is captured by patient tissue can pull the remainder ofthe body 2552 away from the anvil. As this example describes, theanvil-attachable layer 2550 can accommodate an incomplete firing of thesurgical stapler because the connector portion 2560 of theanvil-attachable layer 2550 can be cut by the cutting blade 2570 beforeany staples from a staple cartridge are fired and formed in the body2552 of the layer 2550.

The embodiments described with reference to FIGS. 181-186 can alsoaccommodate an incomplete firing of a surgical stapler. In eachinstance, a cutting blade of the surgical stapler is not needed toseparate the anvil-attachable layer from the staple cartridge. In theembodiments described with reference to FIGS. 181-184, theanvil-attachable layers can be pulled free from their attachments to thestaple cartridge body after a partial firing the surgical instrument. Inthe embodiments described with reference to FIGS. 185 and 186, theanvil-attachable layer is attached to a staple cartridge layer insteadof being attached to the staple cartridge. As described above, thestaple cartridge layer and the anvil-attachable layer are bothimplantable in the patient. Thus, whether the surgical instrument iscompletely fired has no bearing on separating the anvil-attachablelayers in the embodiments described with reference to FIGS. 181-186 froma staple cartridge in a surgical stapler.

In various circumstances, a surgeon can use a second surgical instrumentto detach the anvil-attachable layers, described above with reference toFIGS. 181-184, from a staple cartridge. For example, in variouscircumstances, the surgical stapler is used on delicate tissue, such aslung tissue, the surgeon may want to avoid tugging on the tissue thatcan result from pulling the surgical stapler free from theanvil-attachable layer. In such circumstances, the surgeon can introduceanother surgical instrument, such as a grasping tool, to hold thestapled patient tissue and anvil-attachable layer stationary while thesurgical stapler is removed from the patient. In the various embodimentsof anvil-attachable layers described above with reference to FIGS.185-188, a surgeon may not need a second surgical tool to detach theanvil-attachable layer from the surgical stapler. Referring again to theembodiments described with reference to FIGS. 185 and 186, theanvil-attachable layer 2510 is attached to a staple cartridge layer 2506that is also implanted in the patient. There is no attachment of theanvil-attachable layer to the staple cartridge in the surgical stapler.Therefore, the patient tissue does not need to be tugged or pulled toseparate the anvil-attachable layer from the staple cartridge when thestapler is removed from the patient. Referring again to the embodimentsdescribed with reference to FIGS. 187 and 188, the body 2552 of theanvil-attachable layer 2550 is mechanically detached from the surgicalstapler by a cutting blade 2570 at the beginning of the stroke of thecutting blade. Again, there is no attachment of the body 2552 of theanvil-attachable layer 2550 to the staple cartridge in the surgicalstapler when the surgical stapler is ready for removal from the patientafter cutting and stapling patient tissue. Therefore, the patient tissuedoes not need to be tugged or pulled to separate the body 2552 of theanvil-attachable layer 2550 from the staple cartridge when the stapleris removed from the patient.

Referring primarily to FIGS. 189-190, a compensator 27120 for a sleeve27110 can comprise a body 27122 having a longitudinal protrusion 27124that extends along at least a portion of the body 27122. Thelongitudinal protrusion 27124 can define a longitudinal path along themidline of the body 27122, for example. In various embodiments, thelongitudinal protrusion 27124 can be received by a longitudinal slot inan anvil when the sleeve 27110 is positioned on the anvil. Referringprimarily to FIG. 191, the longitudinal protrusion 27124 can comprise arounded projection. For example, the cross-section of the longitudinalprotrusion 27124 can form an arc and/or partial ring. In otherembodiments, the longitudinal protrusion 27124 can comprise an angularand/or stepped projection. The compensator 27120 can further comprise anedge 27126, which can be straight, bent, fluted, wavy, and/or zigzagged,for example. In various embodiments, the edge 27126 can comprise gaps27128 that can be configured to receive the catch extensions extendingfrom the anvil when the assembled sleeve 27110 is positioned on theanvil.

As outlined herein, a layer, such as a tissue thickness compensator, forexample, can be implanted against tissue by one or more fastenersejected from a staple cartridge. As also outlined herein, in variouscircumstances, the entirety of a staple line can capture at least aportion of the layer against the tissue. For instance, the proximal-moststaples in a staple line can capture at least a portion of the layertherein while the distal-most staples in the staple line can alsocapture at least a portion of the layer therein. In certaincircumstances, a proximal portion of the layer can extend proximallywith respect to the proximal-most staples in the staple line and/or adistal portion of the layer can extend distally with respect to thedistal-most staples in the staple line. In use, a series of layers canbe implanted. In at least one such circumstance, the layers can beimplanted consecutively along a cut line. In some circumstances, thelayers can be implanted such that one layer partially overlaps anotherlayer. For instance, the distal end of a first implanted layer canoverlap with the proximal end of a second implanted layer. Likewise, thedistal end of the second implanted layer can overlap with a proximal endof a third layer, and so forth. As a result, certain fasteners maycapture a portion of two or more layers therein. The presence of two ormore layers captured within a staple can increase the pressure appliedto the tissue captured within the staple and/or increase the rigidity ofthe tissue, especially when several adjacent staples have captured morethan one layer. Referring now to FIGS. 192-194, as described in greaterdetail below, a tissue thickness compensator 11050 can comprise aproximal end 11053 and a distal end 11055 wherein the proximal end 11053and/or the distal end 11055 can comprise one or more strain reliefportions which can reduce the rigidity of the tissue thicknesscompensator 11050 and the rigidity of the tissue being stapled.

Referring again to FIGS. 192-194, the distal end 11055 of the tissuethickness compensator 11050 can comprise one or more slots 11058 definedtherein. The slots 11058 can comprise cuts and/or notches, for example,defined in the tissue thickness compensator 11050. The slots 11058 candefine projections, or tabs, 11056 which can be configured to at leastpartially move and/or flex relative to one another and/or the bodyportion of the tissue thickness compensator 11050. Stated another way,the slots 11058 can provide localized strain relief to the tissuethickness compensator 11050 and the underlying tissue. In certaincircumstances, the tabs 11056 of a first tissue thickness compensator11050 can be overlapped with a proximal end 11053 of a second tissuethickness compensator 11050. In various circumstances, the slots 11058can permit the first tissue thickness compensator 11050 and the secondtissue thickness compensator to pivot relative to one another. Incertain circumstances, referring primarily to FIG. 194, the tabs 11056of a first tissue thickness compensator 11050 can be overlapped with thetabs 11056 of a second tissue thickness compensator 11050. In variouscircumstances, the slots 11058 in the overlapped distal ends 11055 canfurther reduce the rigidity within the underlying tissue. Although theillustrated embodiment of tissue thickness compensator 11050 onlycomprises an arrangement of tabs 11057 and slots 11058 on one endthereof, a tissue thickness compensator may comprise an arrangement oftabs 11057 and slots 11058 on both ends thereof, for example.

In certain embodiments, further to the above, each tab 11056 cancomprise a tapered profile. For instance, each tab 11056 can comprise abase attached to the body of the tissue thickness compensator 11050having a base width and a free end on the opposite end thereof having anend width, wherein the base width can be wider than the end width. Incertain embodiments, the end width can be wider than the base width.Referring primarily to FIG. 194, an end 11055 can comprise a pluralityof tabs 11056 having different configurations. For instance, the tabs11056 can have different lengths. As illustrated in FIG. 194, anend-most tab 11056 a can have a first length, a second tab 11056 b canhave a second length which is longer than the first length, a third tab10056 c can have a third length which is longer than the second length,a fourth tab 10056 d can have a fourth length which is longer than thethird length, a fifth tab 10056 e can have a fifth length which islonger than the fourth length, and a sixth tab 10056 f can have a sixthlength which is longer than the fifth length, for example. In such anembodiment, the tabs 10056 can become progressively shorter toward thedistal end of the tissue thickness compensator 10050. In otherembodiments, the lengths of the tabs 10056 can be arranged in any othersuitable arrangement.

In various circumstances, further to the above, a layer can compriseedges which define the perimeter of the layer. These edges may bestraight, substantially straight, linear, and/or substantially linear,in certain circumstances. In some such circumstances, the layer edgesmay impinge on and/or otherwise affect the surrounding tissue. Also, insome such circumstances, the edges may be rigid and may rigidly supportthe tissue. In effect, certain portions of the tissue may be unsupportedby the layer which are adjacent to other portions of the tissue whichare rigidly supported by the layer without transition therebetween.Referring to FIGS. 192-194 once again, the perimeter of the tissuethickness compensator 11050 can include a contoured configuration whichcan provide a region of transitional rigidity to the underlying tissue.The perimeter of the tissue thickness compensator 11050 can comprise aplurality of notches or recesses 11059 defined therein which can definetabs 11057. Similar to the above, the tabs 11057 can extend from thebody of the tissue thickness compensator 11050 and can move relativethereto. Also similar to the above, each tab 11057 can comprise a baseend attached to the body of the tissue thickness compensator 11050 andfree end which is movable relative to the base end. In certaincircumstances, the free end of a tab 11057 can have a width which isnarrower than the width of the base end of the tab 11057 while, in othercircumstances, the free end of a tab 11057 can have a width which iswider than the width of the base end of the tab 11057. The tabs 11057can comprise any suitable configuration such as a semi-circular, or anat least partially arcuate, configuration, for example. As a result ofthe above, the tissue underlying and/or fastened to the body portion ofthe tissue thickness compensator 11050 can be rigidly supported by thebody portion, the tissue underlying and/or fastened to the tabs 11057can be less than rigidly supported by the tabs 11057, and the tissueadjacent to the tabs 11057, but not underlying the tabs 11057, may beunsupported by the tissue thickness compensator 11050.

Referring now to FIGS. 195 and 196, a staple cartridge assembly 11100can comprise a cartridge body 11110 and a tissue thickness compensator11150 attached to the cartridge body 11110. The cartridge assembly 11100can further comprise one or more attachment members 11160 configured toreleasably hold the tissue thickness compensator 11150 to the cartridgebody 11110. In at least one circumstance, each attachment member cancomprise a strap which extends around the cartridge body 11110 and thetissue thickness compensator 11150. In use, further to the above, afiring member 10030 can be advanced through the staple cartridge 11100to incise the tissue thickness compensator 11150, fire the staples atleast partially stored in the cartridge body 11110, and sever theattachment members 11160. The tissue thickness compensator 11150 cancomprise a first, or proximal, end 11157 and a second, or distal, end11155. The distal end 11155 can comprise an elongate projection 11156extending from a body portion 11153 of the tissue thickness compensator11150. As illustrated in FIG. 195, the elongate projection 11156 canextend distally with respect to the distal-most attachment member 11160.In at least the illustrated embodiment, the cartridge body 11110 cancomprise a deck 11113 within which staple cavities of the cartridge body11110 can be defined. In various circumstances, the body 11153 of thetissue thickness compensator 11150 can be configured and arranged suchthat it covers the deck 11113 and the staple cavities defined in thecartridge body 11110. In at least some circumstances, as alsoillustrated in FIG. 195, the elongate projection 11156 can extenddistally from the deck 11113 and extend distally with respect to thestaple cavities defined in the deck 11113.

In use, further to the above, the tissue thickness compensator 11150 canbe fastened to tissue and can provide tissue thickness compensationproperties, as described herein. Similar to the above, the tissueunderlying the tissue thickness compensator 11150 may be rigidlysupported by the tissue thickness compensator 11150 and the staplessecuring the same whereas the tissue surrounding the tissue thicknesscompensator 11150 may be unsupported by the tissue thickness compensator11150 and may be flexible. In such circumstances, the tissue between theflexible unsupported tissue and the rigidly supported tissue underlyingthe tissue thickness compensator 11150, i.e., the transition tissue, canundergo an undesirable amount of strain. Such strain may negativelyimpact the transition tissue. For instance, when a tissue thicknesscompensator is secured to pulmonary, or lung, tissue, for example, thetissue immediately surrounding the perimeter of the tissue thicknesscompensator, i.e., the perimeter tissue, may tear in certaincircumstances, especially the perimeter tissue adjacent to and/orsurrounding the distal end of the tissue thickness compensator, i.e.,the end perimeter tissue. The distal projection 11156 of the tissuethickness compensator 11150, however, can support the end perimetertissue. Stated another way, the distal projection 11156 can providetransitional support to the end perimeter tissue. Such transitionalsupport can be less than the support provided by the body of the tissuethickness compensator 11150 and can mitigate the change in strainbetween the unsupported tissue and the fully supported tissue underlyingthe tissue thickness compensator 11150. In various circumstances, thedistal projection 11156 can provide an enlarged area in which force canbe transmitted between the unstapled tissue and the stapled tissue. Thedistal projection 11156 can be configured to flex and move with theunsupported tissue and the tissue thickness compensator 11150. Invarious circumstances, the distal projection 11156 can move relative tothe body portion of the tissue thickness compensator 11150 and/or theunsupported tissue.

The tissue thickness compensator 11150, referring again to FIGS. 195 and196, can further comprise a notch 11157 defined in the proximal end11153 thereof. The notch 11157 can be defined between two distallyextending projections 11158. The notch 11157 can comprise any suitableshape, such as a parabolic shape, for example. Similar to the above, thedistally extending projections 11158 can provide transitional support tothe proximal end perimeter tissue. Such transitional support can be lessthan the support provided by the body of the tissue thicknesscompensator 11150 and can mitigate the change in strain between theunsupported tissue and the fully supported tissue underlying the tissuethickness compensator 11150. In various circumstances, the proximalprojections 11158 can provide an enlarged area in which force can betransmitted between the unstapled tissue and the stapled tissue. Theproximal projections 11158 can be configured to flex and move with theunsupported tissue and the tissue thickness compensator 11150. Invarious circumstances, the proximal projections 11158 can move relativeto the body portion of the tissue thickness compensator 11150, eachother, and/or the unsupported tissue. Various alternative embodimentsare envisioned in which more than two projections extend from theproximal end and/or distal end of a tissue thickness compensator.

As illustrated in FIG. 196, two or more tissue thickness compensators11150 can be implanted in an end-to-end manner along a path. In suchcircumstances, the distal end 11155 of a first tissue thicknesscompensator 11150 can overlap with the proximal end 11153 of a secondtissue thickness compensator 11150. Similarly the distal end 11155 ofthe second tissue thickness compensator 11150 can overlap with theproximal end 11153 of a third tissue thickness compensator 11150. Invarious circumstances, the distal projection 11156 of the first tissuethickness compensator 11150 can be aligned, or at least substantiallyaligned, with the recess 11157 of the second tissue thicknesscompensator 11150. Also, in various embodiments, the distal projection11156 and the proximal recess 11558 can be sized and configured suchthat they have substantially the same size and/or shape. In variouscircumstances, a distal projection 11156 can be configured to bepositioned within a proximal recess 11157 of an adjacent tissuethickness compensator 11150.

Turning now to FIGS. 293 and 294, an end effector of a surgical staplinginstrument can comprise a first jaw including a cartridge channel 11390configured to receive a staple cartridge 11300 therein and a second jawincluding an anvil 11391. Similar to the above, the staple cartridge11300 can comprise a cartridge body 11310 and a tissue thicknesscompensator 11350. The staple cartridge 11300 can further comprise atissue abutment member 11355 attached thereto. The tissue abutmentmember 13555, in various circumstances, can be removably attached to thecartridge body 11310. In addition to or in lieu of being removablyattached to the cartridge body 11310, the tissue abutment member 11355can be attached to the tissue thickness compensator 11350. In at leastone such embodiment, the tissue abutment member 11355 may be releasablysecured to the tissue thickness compensator 11350. In use, similar tothe above, fasteners may be deployed from the cartridge body 11310 tosecure the tissue thickness compensator 11350 to tissue T capturedbetween the tissue thickness compensator 11350 and the anvil 11391. Invarious circumstances, fasteners may not penetrate the tissue abutmentmember 11355. In certain other circumstances, fasteners may penetrateand capture at least a portion of the tissue abutment member. 11355therein and secure the tissue abutment member 11355 to the tissue T. Ineither event, similar to the above, at least a portion of the tissueabutment member 11355 can be configured to provide transitional supportbetween the unsupported tissue and the tissue underlying the tissuethickness compensator 11350 which is rigidly supported by the fasteners.The tissue abutment member 11355 can comprise any suitable shape, suchas tongue-shaped, for example. In at least one embodiment, the tissueabutment member 11355 can comprise one or more notches 11358 which candefine tabs 11356 therebetween. Once the tissue thickness compensator11350 has been positioned against and secured to the tissue T, thetissue abutment member 11355 can be configured to flex relative to thetissue thickness compensator 11350 and provide support to the tissueadjacent the distal end of the tissue thickness compensator 11350. Invarious circumstances, the tissue abutment member 11355 can flexrelative to the tissue thickness compensator 11350 and the tabs 11356can flex relative to each other, the body of the tissue abutment member11355, and/or the tissue thickness compensator 11350, for example.

Referring again to FIGS. 293 and 294, at least a portion of the tissueabutment member 11355 can overlap the tissue thickness compensator11350. In various circumstances, such a portion of the tissue abutmentmember 11355 can be attached to the tissue thickness compensator 11350by one or more adhesives, for example. In certain circumstances, atleast a portion of the tissue abutment member 11355 can overlap one ormore staple cavities defined in the cartridge body 11310 such that thestaples ejected from such staple cavities can capture at least a portionof the tissue abutment member 11355 therein and secure the tissueabutment member 11355 to the tissue. At least a portion of the tissueabutment member 11355 can overlap a nose 11311 of the cartridge body11310. In various circumstances, such a portion of the tissue abutmentmember 11355 can be attached to the nose 11311 by one or more adhesives,for example. In other circumstances, such a portion of the tissueabutment member 11355 may not be attached to the nose 11311. Referringprimarily to FIG. 294, at least a portion of the tissue abutment member11355 can overlap a distal portion 11312 of the nose 11311. In variouscircumstances, such a portion of the tissue abutment member 11355 maynot be attached to the distal portion 11312 of the nose 11311. In atleast some circumstances, a gap can be defined between the tissueabutment member 11355. At least a portion of the tissue abutment member11355 can extend freely from the nose 11311 of the cartridge body 11310.In such embodiments, the tissue abutment member 11355 can comprise acantilever.

In use, further to the above, the staple cartridge 11300 can bepositioned on a first side of the tissue T and the anvil 11391 can bepositioned on the second side. The anvil 11391 can then be pivotedtoward the staple cartridge 11300 about a pivot 11392 defined in a shaft11393 of a surgical stapling instrument. Once the anvil 11391 and thestaple cartridge 11300 have been suitably positioned, the staplescontained within the cartridge body 11310 can be ejected therefrom,penetrate the tissue thickness compensator 11350, and secure the tissuethickness compensator 11350 to the tissue T. Thereafter, the anvil 11391can be opened and the end effector can be moved away from the tissue T.In such circumstances, the cartridge body 11310 can be pulled away fromthe tissue thickness compensator 11350 thereby leaving the tissuethickness compensator 11350 behind. Concurrently, the tissue abutmentmember 11355 can detach from the staple cartridge 11300 with the tissuethickness compensator 11350. To the extent that the tissue abutmentmember 11355 is attached to the tissue thickness compensator 11350, thetissue thickness compensator 11350 can hold the tissue abutment member11355 against the tissue. In various circumstances, the tissue abutmentmember 11355 can be biased against the tissue T by the tissue thicknesscompensator 11350. When the tissue moves, expands, and/or flexes, forexample, the tissue abutment member 11355 can flexibly support theunderlying tissue T and distribute forces, stresses, and/or strains overa large area.

Referring again to FIGS. 293 and 294, the end effector of a surgicalinstrument can comprise a tissue abutment member, such as tissueabutment member 11395, for example, attached to the anvil 11391. Invarious circumstances, the tissue abutment member 11395 can be the sameas, or at least substantially the same as, the tissue abutment member11355. In at least one circumstance, the tissue abutment member 11395can comprise notches 11398 defined between tabs 11396. In use, thetissue abutment member 11395 can be attached to the anvil 11391utilizing one or more adhesives, for example, wherein the tissueabutment member 11395 can be positioned against the tissue T when theanvil 11391 is positioned relative to the tissue T and then closed. Whenthe anvil 11391 is reopened after the staples have been fired from thestaple cartridge, the tissue abutment member 11395 can detach from theanvil 11391 and remain attached to the tissue T. In variouscircumstances, at least a portion of the tissue abutment member 11395can be captured within the staples ejected from the cartridge body11310, for example. In at least some such circumstances, the tissueabutment member 11395 can at least partially overlap, or extend over,staple cavities defined in the anvil 11391. In some circumstances, oneor more adhesives, such as activatable adhesives, for example, can belocated on the tissue-contacting surfaces of the tissue abutment member11395 such that the tissue abutment member 11395 adheres to the tissueT. In any event, referring primarily to FIG. 294, one or both of thetissue abutment member 11355 and the tissue abutment member 11395 may beutilized to flexibly support the tissue T. In embodiments where both thetissue abutment member 11355 and the tissue abutment member 11395 areutilized, the tissue abutment members 11355 and 11395 may be comprisedof the same material, or different materials. The tissue abutmentmembers 11355 and 11395 may comprise the same shape and configuration,or different shapes and configurations. The tissue abutment members11355 and 11395 may also comprise the same thickness, or differentthicknesses. Such properties of the tissue abutment members 11355 and11395 can be selected so as to provide a desired support profile to thetissue positioned therebetween. For instance, such properties may beselected such that one of the tissue thickness compensators 11355 and11395 is more rigid than the other. Concurrently, such properties may beselected such that one of the tissue thickness compensators 11355 and11395 is more flexible than the other.

In various circumstances, a tissue thickness compensator can comprise aplurality of layers. For instance, a tissue thickness compensator cancomprise a first layer and a second layer. Such layers can be comprisedof the same materials, or different materials. Some layers can beconfigured to provide different properties to the tissue thicknesscompensator. For instance, a tissue thickness compensator can comprise acompressible first layer that provides tissue thickness compensationproperties and a more rigid second layer which can support the firstlayer. Referring primarily to FIGS. 197 and 198, a tissue thicknesscompensator 11250 can comprise a first layer 11251 and a second layer11252. The second layer 11252 can be compressible and can provide tissuethickness compensation properties. The first layer 11251 can be rigidand can support the second layer 11252. The second layer 11252 can bepositioned against and/or attached to a cartridge body 11210, forexample. In certain circumstances, the first layer 11251 can comprise alongitudinal channel 11253 extending along the length thereof which canbe sized and configured to be releasably retained in a longitudinalknife slot 11215 defined in the cartridge body 11210. In variouscircumstances, the second layer 11252 can be secured to the first layer11251 and held in place by the first layer 11251.

Referring again to FIGS. 197 and 198, compensator 11250 may comprise aplurality of layers. In addition, an outer periphery 11218 of the secondlayer 11252 may be at least partially extended beyond an outer periphery11220 of the first layer 11251. Furthermore, the first layer 11251 andthe second layer 11252 may comprise different degrees of stiffness. Forexample, the second layer 11252 may be configured to be more flexiblethan the first layer 11251. This arrangement may provide tissuethickness compensator 11250 with a sufficiently rigid inner region,comprised from the first layer 11251 and the second layer 11252, whichmay be suitable to provide adequate support for staples 11260, and asufficiently flexible outer region, comprised from the second layer11252, which may be suitable to provide sufficient flexibility to softenthe impact upon tissue T, for example, during and/or after the capturingof the tissue T and the tissue thickness compensator 11250 by thestaples 11260. Layers 11251 and 11252 can be joined together, forexample, by an adhesive. Other attachment means for attaching the firstlayer 11251 to the second layer 11252 are contemplated within the scopeof the current disclosure.

Further to the above, the first layer 11251 may include an inner portion11254 and an outer portion 11256 at least partially surrounding theinner portion 11254, wherein the outer portion 11256 may be configuredto be more flexible than the inner portion 11254. For example, the outerportion 11254 may comprise a plurality of slits 11210 which may increasethe flexibility of the outer portion 11254. Furthermore, as describedabove, the second layer 11252 may be configured to be more flexible thanthe first layer 11251. This arrangement may provide tissue thicknesscompensator 11250 with three regions of different rigidity including afirst inner region having the most rigidity, the inner region beingcomprised of inner portion 11254 of the first layer 11251 and the secondlayer 11252, a middle region having an intermediate rigidity, the middleregion being comprised of outer portion 11256 of first layer 11251 andthe second layer 11252, and a third outer region having the leastrigidity, the third region being comprised solely of the second layer11252.

The second layer 11252 of tissue thickness compensator 11250 cancomprise a woven structure which may include a plurality of fibers whichmay be woven into the woven structure. The woven structure may providethe second layer 11252 with sufficient flexibility to soften the impactupon tissue T, for example, during and/or after the capturing of thetissue T and the tissue thickness compensator 11250 by staples 11260.Furthermore, the outer periphery 11218 can be comprised of fibers whichcan provide an atraumatic tissue contacting surface to minimize impactupon tissue T, as described above. The woven structure and fibers can becomprised of biocompatible materials. Furthermore, the woven structureand/or fibers can be comprised from a bioabsorbable material such asPLLA, PGA, PCL, and/or combinations thereof, for example.

Referring to FIGS. 199-201, a staple cartridge channel can be configuredto receive a staple cartridge 1060 which can comprise a cartridge body1062, a cartridge deck 1064, and a support 1065. In addition, a tissuethickness compensator such as, for example, tissue thickness compensator1100 may be removably positioned against or adjacent cartridge deck1064, as illustrated in FIG. 199.

Referring again to FIGS. 199-201, a tissue thickness compensator may beconfigured to be absorbed after implantation in a patient. Theabsorption process may initially reduce the tissue thickness compensatorinto smaller pieces which may include rough edges that may haveundesirable effects on surrounding tissue T. To mitigate these effects,tissue thickness compensator 1100 may be at least partially assembledfrom a plurality of pieces 1140, which each may have atraumatic outerperipheries and may be joined together to form a single structure, asillustrated in FIG. 201. Pieces 1140 can be joined to form tissuethickness compensator 1100 in a manner such that the absorption processmay first reduce tissue thickness compensator 1100 into pieces 1140thereby minimizing the presence of rough edges. For example, pieces 1140may comprise circular profiles and may be joined together by thermalbonding to form tissue thickness compensator 1100. Other profiles andother means for joining pieces 1140 are contemplated within the scope ofthe present disclosure. In one example, pieces 1140 can be joinedtogether by an adhesive 1143 (See FIG. 200) configured to be absorbedfaster than pieces 1140 to allow separation of the pieces 1140 in aninitial stage of the absorption process. As illustrated in FIG. 200,pieces 1140 can be arranged in an overlapping array wherein an endportion of one of the pieces 1140 may overlap with an end portion ofanother one of the pieces 1140 such that the two end portions of thepieces 1140 are releasably attached to each other, for example, by anadhesive. Under certain circumstances, pieces 1140 can be arranged inanother overlapping array wherein one of the pieces 1140 can bepositioned over and releasably attached to a plurality of pieces 1140,as illustrated in FIG. 201.

Referring to FIGS. 202-204, as described above, a tissue thicknesscompensator may be configured to be absorbed after implantation in apatient and the absorption process may initially reduce the tissuethickness compensator into random smaller pieces. Guiding the absorptionprocess to yield small pieces with atraumatic outer edges can beachieved, as described above, by starting with small pieces havingatraumatic outer edges. Another approach may include modifying thetissue thickness compensator in such a manner that allows its separationinto smaller pieces having atraumatic peripheries in an initial stage ofthe absorption process. For example, as illustrated in FIG. 202, atissue thickness compensator 1200 may comprise a pattern such as pattern1212, for example, which can be molded or carved into the tissuethickness compensator 1200 to yield, for example, a plurality ofcircular shaped portions 1210. The portions 1210 may be defined byreducing the thickness of tissue thickness compensator 1200 alongcircumferences 1214 of the circular shaped portions 1210, as illustratedin the cross-sectional view in FIG. 202A. In result, a faster absorptionalong the circumferences 1214 of circular shaped portions 1210 may occurwhich may lead to a separation of the circular shaped portions 1210 fromeach other in an initial stage of the absorption process. Patternscomprising portions with other geometrical shapes with atraumatic outerperipheries are contemplated within the scope of the current disclosure.For example, as illustrated in FIG. 203, tissue thickness compensator1200′ may comprise a pattern 1216 comprising portions 1218 which mayinclude profiles that extend longitudinally in a wave-like profile alonga length of tissue thickness compensator 1200′. In another example, asillustrated in FIG. 204, tissue thickness compensator 1200″ may comprisea pattern 1220 which may include hexagonal shaped portions 1222.

Referring to FIG. 205, as described above, a tissue thicknesscompensator, such as tissue thickness compensator 1250, may be capturedalong with tissue T by staples, such as staples 1002, for example, andmay be configured to be reduced into atraumatic pieces, such as pieces1226, for example, in an initial stage of the absorption process afterimplantation in a patient. Upon separation, pieces 1226 can move and/orslide relative to each other which may impact surrounding tissue T. Tominimize relative motion between pieces 1226, fired staples 1002 can bespatially arranged onto tissue thickness compensator 1250 such that astaple 1002 may capture multiple pieces 1226, as illustrated in FIG.205. This may also aid in maintaining tissue thickness compensator 1250in a substantially singular structure even after pieces 1226 areseparated from each other in the initial stage of the absorptionprocess. As such, the tissue thickness compensator 1250 may continue toprovide support for tissue T captured by staples 1002 after pieces 1226are separated from each other in the initial stage of the absorptionprocess.

Further to the above, referring now to FIG. 206, yet another approachcan be taken to guide the absorption process of a tissue thicknesscompensator to yield small pieces with atraumatic outer edges. Forexample, as illustrated in FIG. 206, a tissue thickness compensator suchas tissue thickness compensator 1300 may comprise a plurality of slits1310 which can be strategically positioned to improve the flexibility oftissue thickness compensator 1300, as described above. In addition,slits 1310 may partially divide tissue thickness compensator 1300 into aplurality of portions 1312 which may separate from each other during aninitial stage of the absorption process. Slits 1312 can reduce the widthof tissue thickness compensator 1300 along outer peripheries 1314 ofportions 1312, as illustrated in FIG. 206. This reduction in width maylead to faster absorption along the outer peripheries 1314 of portions1312, which can result in reducing tissue thickness compensator 1300into separate portions 1312 during the initial stage of the absorptionprocess.

Referring to FIGS. 207A and 207B an end effector of a surgical staplinginstrument can comprise a first jaw and a second jaw, wherein at leastone of the first jaw and the second jaw can be configured to be movedrelative to the other. In certain embodiments, the end effector cancomprise a first jaw including a staple cartridge channel 1010 and asecond jaw including an anvil 1012 (FIG. 207B), wherein the anvil 1012can be pivoted toward and/or away from the staple cartridge channel1010, for example. The staple cartridge channel 1010 can be configuredto receive a staple cartridge 1020, for example, which can be removablyretained within the staple cartridge channel 1010. Other embodiments mayinclude staple cartridges that are not readily removable from thecartridge channel 1010. The staple cartridge 1020 can comprise acartridge body 1022, a cartridge deck 1024, and a layer 1000 wherein, asillustrated in FIG. 207A, layer 1000 may be removably positioned againstor adjacent cartridge deck 1024.

Similar to other embodiments described herein, referring again to FIGS.207A and 207B, the cartridge body 1022 can comprise a plurality ofstaple cavities 1026 and a staple 1002 positioned within each staplecavity 1026. Also similar to other embodiments described herein, thestaples 1002 can be supported by staple drivers 1028 positioned withinthe cartridge body 1022 wherein a sled and/or firing member, forexample, can be advanced through the staple cartridge 1020 to lift thestaple drivers 1028 upwardly within the staple cavities 1026 and ejectthe staples 1002 from the staple cavities 1026, as illustrated in FIG.207B. Tissue T and/or layer 1000 can be captured by staples 1002, asillustrated in FIG. 207B, as staples 1002 are ejected from the staplescavities 1026.

Layer 1000 may be comprised of a biocompatible material. In addition,layer 1000 can be comprised of a bioabsorbable material such as PLLA,PGA, PCL, and/or combinations thereof, for example. In at least oneembodiment, layer 1000 can comprise a tissue thickness compensator whichmay include internal compression features designed to compensate fortissue T thickness when layer 1000 and tissue T are captured by staples1002, as described above.

Referring again to FIG. 207B, layer 1000 can include a tissue contactingsurface 1003 which can be configured to reduce slippage between thelayer 1000 and the tissue T positioned thereagainst. Pressure exertedagainst the tissue T in contact with the tissue contacting surface 1003may depend in part on the contact area between the tissue T and thetissue contacting surface 1003. Since pressure is reversiblyproportional to area, reducing the contact area may yield higherpressure against the tissue T and in turn may yield better slippageprotection. The tissue contacting surface 1003 may include a pluralityof cleats 1030 comprising small contact areas, wherein the cleats 1030may reduce slippage between the layer 1000 and the tissue T positionedthereagainst. Layer 1000 can be manufactured with cleats 1030, forexample, by compression molding techniques. Alternatively, cleats 1030can be formed onto tissue contacting surface 1003 after layer 1000 ismanufactured, for example, by laser and/or chemical etching techniqueswhich may yield a plurality of protruding structures. Furthermore,cleats 1030 may comprise micrometer and/or nanometer scale structuresformed onto tissue contacting surface 1003 using, for example,photolithography techniques which may generally use a pre-fabricatedphotomask as a master from which a final pattern of micrometer and/ornanometer scale cleats can be derived. Other techniques for formingmicrometer and/or nanometer scale cleats 1030 can be utilized and arecontemplated within the scope of the current disclosure. In one example,electron beam lithography can be utilized to create cleats 1030.

Referring now to FIGS. 207C-224, cleats 1030 can comprise a plurality ofshapes. For example, as illustrated in FIG. 207C, tissue contactingsurface 1003 may include pillar-shaped cleats 1038 which may includesquare and/or rectangle bases and substantially perpendicular sidesextending generally away from tissue contacting surface 1003. Inaddition, pillar-shaped cleats 1038 may terminate at generally narrowtop portions, or tips 1040, as illustrated in cross-sectional view inFIG. 208. Furthermore, tissue contacting surface 1003 may includecone-shaped cleats 1032, as illustrated in FIG. 218, pyramid-shapedcleats 1034, as illustrated in FIG. 219, and/or dome-shaped cleats 1042,as illustrated in FIG. 211. The pyramid-shaped cleats 1034 may includesquare and/or triangular bases and sloping sides that may extendgenerally away from tissue contacting surface 1003 and terminate at topportions 1036, as illustrated in the cross-sectional view in FIG. 220.

Cleats 1030 can be spatially arranged onto tissue contacting surface1003 in a predetermined pattern or array. For example, cleats 1030 canbe spatially arranged onto tissue contacting surface 1003 in multiplerows which may extend longitudinally along a length of surface 1003 inparallel to each other. Cleats 1030 can also be spatially arranged incircles. For example, cleats 1030 can be arranged in concentric circles.Alternatively, cleats 1030 can be randomly positioned onto tissuecontacting surface 1003.

Further to the above, tissue contacting surface 1003 may include cleats1030 comprising multiple shapes, multiple heights, and/or multiplespatial arrangements to provide various degrees of slippage protectionalong various regions of the tissue contacting surface 1003. Forexample, greater slippage protection may be needed at and/or aroundregions of tissue contacting surface 1003 where staples 1002 areconfigured to penetrate and capture tissue T.

Referring to FIGS. 209, 210, and 215-217, layer 1000 may comprise linearprotrusions 1044 which can be disposed onto the tissue contactingsurface 1003. Linear protrusions 1044 may extend longitudinally. Forexample, linear protrusions 1044 may extend in parallel with each other,along a length of the layer 1000, as illustrated in FIG. 209.Alternatively, linear protrusions 1044 may extend along a width of thelayer 1000, as illustrated in FIG. 215. Furthermore, longitudinal andtransverse linear protrusions 1044 may cross paths. For example, asillustrated in FIG. 217, a first pattern 1046 of the linear protrusions1044 may extend in parallel in a first direction on tissue contactingsurface 1003, and a second pattern 1048 of linear protrusions 1044 mayextend in parallel in a second direction on tissue contacting surface1003, wherein the first direction can be perpendicular, or substantiallyperpendicular, to the second direction. Furthermore, linear protrusions1044 may comprise substantially uniform cross-sectional areas, asillustrated in FIG. 210. Alternatively, linear protrusions 1044 maycomprise different cross-sectional areas (not shown). In certaincircumstances, the first pattern 1046 and the second pattern 1048 may becontinuous or intermittent.

Further to the above, layer 1000 may include non-linear protrusionswhich can be disposed onto the tissue contacting surface 1003 alone orin combination with linear protrusions 1044. Furthermore, linearprotrusions 1044 and/or the non-linear protrusions can be disposed ontothe tissue contacting surface 1003 in combination with cleats 1030 toproduce a desired degree of slippage protection.

Referring to FIGS. 213 and 214, layer 1000 may comprise a plurality ofdepressions 1050 which can be carved into the tissue contacting surface1003, as illustrated in FIG. 223. Depressions 1050 may comprisesubstantially uniform socket shapes, as illustrated in FIG. 224.Alternatively, depressions 1050 may comprise different depths which mayprovide various degrees of slippage protection along various regions ofthe tissue contacting surface 1003. Generally, a greater depth of aparticular depression may yield a greater flexibility of the regionwhere the depression lies and a greater collapsibility of such region.Furthermore, as discussed above with respect to Cleats 1030, depressions1050 may comprise a plurality of shapes and/or spatial arrangements. Inaddition, layer 1000 may comprise combinations of depressions 1050 andcleats 1030 spatially arranged on tissue contacting surface 1003. Incertain circumstances, cleats 1030 and depressions 1050 may be arrangedin alternating patterns.

Referring again to FIGS. 223 and 224, layer 1000 may comprise lineardepressions 1052 which, similar to linear protrusions 1044 (describedabove), may extend longitudinally, for example in parallel with eachother, along a length of the layer 1000, as illustrated in FIG. 223.Furthermore, layer 1000 may comprise combinations of linear depressions1052 and linear protrusions 1044 spatially arranged onto tissuecontacting surface 1003, for example in an alternating pattern.Furthermore, referring now to FIGS. 221 and 222, the combinations oflinear depressions 1052 and linear protrusions 1044 can be arranged in acorrugated pattern 1054, as illustrated in FIG. 221.

Referring now to FIGS. 244-246, a tissue thickness compensator, such ascompensator 22320, for example, can comprise a plurality of firstcavities 22322 a and a plurality of second cavities 22322 b which can bealigned with staple forming pockets 22062 a and 22062 b, respectively.Referring primarily to FIG. 245, the staple forming pockets 22062 a and22062 b may be defined in separate stepped surfaces on the anvil 22060.More particularly, the forming pockets 22062 a can be defined in firstsurfaces 22069 a of anvil 22060 and the forming pockets 22062 b can bedefined in second surfaces 22069 b wherein the first surfaces 22069 acan be positioned offset, or higher, with respect to the second surfaces22069 b, for example. The first cavities 22322 a of the tissue thicknesscompensator 22320 can be larger than the second cavities 22322 bwherein, in at least one such embodiment, the first cavities 22322 a canextend higher than the second cavities 22322 b. As a result of theabove, the first cavities 22322 a can extend upwardly into the firststaple forming pockets 22062 a while, concurrently, the second cavities22322 b can extend upwardly into the second staple forming pockets 22062b. The first cavities 22322 a and/or the second cavities 22322 b can beconfigured to contain a medicament.

Further to the above, the first cavities 22322 a can be arranged incertain rows while the second cavities 22322 b can be arranged indifferent rows. The cavities 22322 a and/or the cavities 22322 b can beconfigured to fit snugly within staple forming pockets 22062 a and/or22062 b, respectively. Furthermore, the compensator 22320 can beassembled to the anvil 22060 such that the second layer 22327 of thecompensator 22320 is positioned against the second surfaces 22069 b ofthe anvil 22060. Referring now to FIGS. 247 and 248, the compensator22320 can be positioned adjacent to the anvil 22060 such that thecompensator 22320 can abut the anvil 22060 when the anvil 22060 isdisplaced toward the staple cartridge 22000 to compress the tissue Ttherebetween.

Referring now to FIGS. 224A and 2248, similar to the above, layer 1000can also be positioned adjacent to the anvil 1012 such that the layer1000 can abut the anvil 1012 when the anvil 1012 is displaced toward thestaple cartridge 1020 to compress the tissue T therebetween. Alsosimilar to the above, the layer 1000 may be captured by staples 1002 asstaples 1002 are ejected from the staple cavities 1026 by staple drivers1028. In particular, as illustrated in FIGS. 224A and 224B, staples 1002may each comprise a base 1060, a first deformable member 1062 comprisinga first tip 1063 and a second deformable member 1064 comprising a secondtip 1065 which, along with the first tip 1063, may penetrate throughlayer 1000 to reach their respective forming pockets 1066 and 1068 asstaples 1002 are ejected from the staple cavities 1026 by staple drivers1028. In addition, tips 1063 and 1065 may each penetrate through layer1000 a second time as the tips 1063 and 1065 are guided on a return pathout of the forming pockets 1066 and 1068, respectively.

Referring again to FIG. 224A, layer 1000 may include portions 1070 whichmay comprise a reduced thickness relative to the remainder of the layer1000. For example, as illustrated in FIG. 224A, layer 1000 may comprisea substantially uniform thickness “A” and portions 1070 may comprise athickness smaller than thickness “A.” In addition, layer 1000 can bealigned with staple cartridge 1020 such that upon firing staples 1002the tips 1063 and 1065 of staples 1002 may penetrate through tissue Tand the full thickness “A” of layer 1000 as the tips 1063 and 1065 ofthe deformable members 1062 and 1064 travel toward the respectivepockets 1066 and 1068 and may penetrate through the reduced thickness ofportions 1070 as they are guided out of the pockets 1066 and 1068,respectively. The reduced thickness of portions 1070 may improve therepiercing of tips 1063 and 1065 into the tissue T on the return pathsof tips 1063 and 1065 from pockets 1066 and 1068, respectively.

Referring now to FIG. 224B, layer 1000 may comprise protrusions 1080which may comprise an increased thickness relative to the remainder ofthe layer 1000. For example, as illustrated in FIG. 224B, layer 1000 maycomprise a substantially uniform thickness “A” and protrusions 1080 maycomprise a thickness “A+B” greater than thickness “A”. Layer 1000 can bealigned with staple cartridge 1020 such that upon firing staples 1002the tips 1063 and 1065 of staples 1002 may penetrate through tissue Tand the thickness “A” of layer 1000 as the tips 1063 and 1065 of thedeformable members 1062 and 1064 travel toward the respective pockets1066 and 1068. In addition, tips 1063 and 1065 of staples 1002 maypenetrate through the thickness “A” of layer 1000 as they are guided outof the pockets 1066 and 1068 respectively thereby wrapping, orsubstantially wrapping, deformable members 1062 and 1064 at leastpartially around protrusions 1080. In other words, tissue T andprotrusions 1080 may be captured between each of deformable members 1062and 1064 and bases 1060 of staples 1002. Further to the above,protrusions 1080 can be arranged in rows and can be configured to fitsnugly within the staple forming pockets of anvil 1020. For example, asillustrated in FIG. 224B, protrusions 1080 can comprise curved profileswhich can be configured for mating engagement with forming pockets 1066and 1068.

As described above, certain embodiments of surgical staplers may includea layer, such as a buttress material and/or a tissue thicknesscompensator, arranged on a surface of an anvil of the end effector. Thelayer can be susceptible to movement and/or misalignment. For example,the layer may be moved relative to the anvil if the layer is draggedacross patient tissue while a surgeon positions the surgical staplerprior to stapling tissue. In certain embodiments, the layer can includereleasable retention features for attaching the layer to the anvil sothat the layer remains aligned with the anvil until after the surgicalstapler is fired. In certain embodiments, the releasable retentionfeatures can be implantable in the patient.

In certain embodiments, referring now to FIGS. 225-227, ananvil-attachable layer 33420, such as a buttress material and/or atissue thickness compensator, can comprise a shell 33426, a cavity 33424defined in the shell 33426, and a core 33425 positioned within thecavity 33424. In at least one such embodiment, the shell 33426 cancomprise a film body formed from a continuous extruded shape and thecore 33425 can comprise a fibrous medicament core, such as ORC, forexample. In at least one embodiment, the shell 33426 can comprise one ormore flexible legs 33423 which can be configured to extend into a knifeslot 22063 defined in the anvil 22060 and releasably retain theanvil-attachable layer 33420 to the anvil 22060.

In certain other embodiments, referring to FIGS. 244-248, ananvil-attachable layer 22320, such as a buttress material and/or atissue thickness compensator, can be attached to an anvil 22060. In atleast one embodiment, the anvil-attachable layer 22320 can includecavities 22322 a and/or cavities 22322 b that can be configured to fitsnugly within staple forming pockets 22062 a and/or 22062 b,respectively. The snug fit can releasably retain the anvil-attachablelayer 22320 relative to the anvil 22060. In certain embodiments, theanvil-attachable layer 22320 can be assembled to the anvil 22060 suchthat a second layer 22327 of the anvil-attachable layer 22320 ispositioned against the second surfaces 22069 b of the anvil 22060. Incertain other embodiments, referring now to FIGS. 247 and 248, theanvil-attachable layer 22320 can be positioned adjacent to the anvil22060 such that the anvil-attachable layer 22320 can abut the anvil22060 when the anvil 22060 is displaced toward the staple cartridge22000 to compress the tissue T therebetween.

Referring to FIGS. 228-234, a retainer can be used to align and attachan anvil-attachable layer to an anvil of an end effector. Referringprimarily to FIGS. 229 and 230, an anvil-attachable layer 2030 caninclude a body 2034 and a protrusion 2036 extending from the body 2034.Referring to FIGS. 231-234, the protrusion 2036 can engage a slot 2048,such as a knife slot, in an anvil 2042 of an end effector. In certainembodiments, the protrusion 2036 can be wider than the slot 2048 suchthat the protrusion 2036 is compressed when inserted into the slot 2048.In certain embodiments, the protrusion 2036 can be deformed such that itbulges outwardly and presses against surfaces of the slot 2048. Acompressive force between the protrusion 2036 and the slot 2048 canprovide a retention force that holds the anvil-attachable layer 2030relative to the anvil 2042.

The anvil-attachable layer 2030 can be releasably attached to a retainer2000. The retainer 2000 can align the anvil-attachable layer 2030 withthe anvil 2042 and attach the anvil-attachable layer 2030 to the anvil2042. Embodiments of the retainer 2000 can include a cover 2006 and tabs2008, 2010 (tab 2010 illustrated in FIGS. 228-230) extending therefrom.As illustrated in FIGS. 229 and 230, the tabs can engage and releasablyhold a staple cartridge 2020 to the retainer 2000. The retainer also caninclude a grip portion 2002 extending from the cover 2006 that a usermay grasp to insert the retainer 2000, the staple cartridge 2020, andthe anvil-attachable layer 2030 into a staple cartridge channel 2040 ofan end effector.

The retainer 2000 can also include tabs 2014 that extend from the cover2006. In certain embodiments, the retainer 2000 can include two tabs2014, one tab extending from each lateral side of the cover 2006. As canbe best seen in FIG. 228, each tab 2014 can include an inward-facinggroove 2016 and an inward-facing angled surface 2018. Referring to FIGS.229 and 230, lateral edges of the anvil-attachable layer 2030 can engagethe grooves 2016 in the tabs 2014. When the anvil-attachable layer 2030is engaged in the slots 2016 of the retainer 2000, in variousembodiments, the anvil-attachable layer 2030 and the cover 2006 of theretainer 2000 can define a gap therebetween. The anvil-attachable layer2030 can be arranged on the retainer 2000 such that the protrusion 2036of the layer 2030 extends away from the retainer 2000. As best seen inFIGS. 228 and 231, the retainer 2000 can also include a raised ridge2022 extending from the cover 2006. As best shown in FIG. 231, theraised ridge 2022 of the retainer 2000 can be aligned with theprotrusion 2036 of the anvil-attachable layer 2030.

In use, a surgeon, nurse, clinician or other user, can insert the staplecartridge 2020 into the staple cartridge channel 2040 of the endeffector, close the anvil on the retainer to release theanvil-attachable layer from the retainer and attach the layer to theanvil, and then remove the retainer from the end effector. Referringprimarily to FIGS. 231-234, the user can grasp the retainer 2000 by thegrip portion 2002 and insert the staple cartridge 2020 into a staplecartridge channel 2040 of the end effector. As the staple cartridge 2020is being inserted into the staple cartridge channel 2040, tabs 2008 ofthe retainer 2000 can engage the staple cartridge channel 2040 of theend effector. FIG. 231 illustrates the staple cartridge 2020 loaded intothe staple cartridge channel 2040 with the retainer 2000 andanvil-attachable layer 2030 on top of the staple cartridge 2020. As alsoillustrated in FIG. 231, the anvil 2042 of the end effector ispositioned above the anvil-attachable layer 2030 and the retainer 2000.Referring now to FIG. 232, the anvil 2042 can be moved toward theretainer 2000 and the anvil-attachable layer 2030. As the anvil 2042 ismoved, a surface 2044 of the anvil 2042 can contact the body 2034 of theanvil-attachable layer 2030. Furthermore, a slot 2046, such as a knifeslot, of the anvil 2042 can engage the ridge 2036 of theanvil-attachable layer 2030. Also, as the anvil 2042 is moved toward thestaple cartridge 2020, lateral edges 2050 of the anvil 2042 can engagethe inward-facing angled surfaces 2018 of the film-holding tabs 2014,pushing the tabs 2014 outward such that the inward-facing grooves 2016move away from the lateral edges of the anvil-attachable layer 2030.

Continued movement of the anvil 2042 toward the anvil-attachable layer2030 can push the anvil-attachable layer 2030 toward the cover 2006 ofthe retainer 2000. Also, as the anvil 2042 continues to move toward thestaple cartridge 2020, the raised ridge 2022 of the retainer 2000 cansupport the protrusion 2036 of the anvil-attachable layer 2034 as itengages the slot 2046 of the anvil 2042. As described above, the raisedridge 2022 of the retainer 2000 can deform the protrusion 2036 of theanvil-attachable layer 2030 such that the exterior dimensions of theprotrusion 2036 of the anvil-attachable layer 2030 extend outwardly. Putdifferently, as the ridge 2036 of the anvil-attachable layer 2030 entersthe slot 2046 of the anvil 2042, the raised ridge 2022 of the retainer2000 can press into the anvil-attachable layer 2030 under the protrusion2036, causing the protrusion 2036 to bulge out and/or expand into theslot 2046 of the anvil 2042. The resulting contact between the expandedprotrusion 2036 and the slot 2046 can hold the ridge 2036 of theanvil-attachable layer 2030 within the slot 2046. The slot 2046 caninclude lips 2048 that can capture at least a portion of the protrusion2036, further retaining the protrusion 2036 within the slot 2046 of theanvil 2042.

Referring now to FIG. 233, when the anvil 2042 is moved away from theretainer 2000, the anvil-attachable layer 2030 is carried away from theretainer 2000 with the anvil 2042. As illustrated in FIG. 234, after theanvil 2042 and the anvil-attachable layer 2030 have moved away from theretainer 2000, the retainer 2000 can be removed from the end effector,leaving the anvil-attachable layer 2030 and the staple cartridge 2020 inthe end effector.

Referring again to FIGS. 229 and 230, in certain embodiments, a proximalend 2032 of the anvil-attachable layer 2030 can be attached to thestaple cartridge 2020. For example, the anvil-attachable layer 2030 maybe attached to the staple cartridge 2020 by adhesive, tack welding,and/or heat staking. In various embodiments, the anvil-attachable layer2030 can detach from the staple cartridge 2020 after theanvil-attachable layer 2030 is attached to the anvil 2042 and the anvilis reopened. In various other embodiments, the anvil-attachable layer2030 can remain attached to the staple cartridge 2020 until after thestaples in the staple cartridge have been fired and the anvil-attachablelayer 2030 is captured within the fired staples.

FIG. 235 illustrates the anvil-attachable layer 2030 separate from theretainer 2000. FIGS. 236 and 237 illustrate other embodiments ofanvil-attachable layers. FIG. 236 illustrates an embodiment of ananvil-attachable layer 2060 that includes a body 2064 and discreteprotrusions 2062 extending therefrom. FIG. 237 illustrates anotherembodiment of an anvil-attachable layer 2070 that includes a body 2074with discrete protrusions 2072 extending therefrom. For example, eachdiscrete protrusion 2072 can include a peg 2073 extending from the bodyof the anvil-attachable layer 2070 and a cap 2075 extending from the peg2073. In certain embodiments, the cap 2075 can have larger dimensionsthan the peg 2073 so that the cap extends over the lateral edges 2048 inthe slot 2046 in the anvil 2042 when the protrusions 2072 are insertedinto the slot 2046.

Referring now to FIGS. 238-243, various embodiments of anvil-attachablelayers can include one or more deployable attachment features that canbe formed in the body of the anvil-attachable layer. FIGS. 238-240illustrate an embodiment of an anvil-attachable layer 2080 that includesa body 2082 and an array of deployable attachment features 2084 formedin the body 2082. Each deployable attachment feature 2084 can be formedin the body 2082 by forming apertures 2085 in the body 2082. Eachdeployable attachment feature 2084 can include a longitudinal portion2086 attached to the body 2082 and a lateral portion 2088 attached tothe longitudinal portion 2086. In various embodiments, the longitudinalportion 2086 can be attached to the body 2082 by a hinge 2087. Theaperture 2085 surrounding each deployable attachment feature 2084 andthe hinge 2087 can permit movement of the deployable attachment features2084 between an undeployed configuration and a deployed configured,described in greater detail below. In various other embodiments, thehinge 2087 can be absent. In such embodiments, the deployable attachmentfeatures 2084 can be bent about the longitudinal portions 2086, forexample, to move between the undeployed configuration and the deployedconfiguration.

FIG. 238 illustrates the deployable attachment features 2084 in anundeployed configuration, wherein each of the deployable attachmentfeatures 2084 lies substantially in a plane defined by the body 2082 ofthe anvil-attachable layer 2084. FIG. 239 illustrates the deployableattachment features 2084 in a deployed configuration, wherein eachdeployable attachment feature 2084 extends out of the plane defined bythe body 2082 of the anvil-attachable layer 2080. For example, thedeployable attachment features 2084 can rotate about the hinges 2087 toextend out of the plane defined by the body 2082. As illustrated in FIG.240, the deployable attachment features 2084 can be deployed into a slot2046 of an anvil 2042. When deployed, the longitudinal portion 2086 ofthe deployable attachment feature 2084 can extend into the slot 2046 ofthe anvil 2042 and the lateral portion 2088 can extend further into theslot 2046. In various circumstances, the lateral portion 2088 of thedeployable attachment feature 2084 can engage a lip 2048 in the slot2046 to provide for stronger retention between the anvil-attachablelayer 2080 and the anvil 2042. Furthermore, engagement between thelateral portion 2088 of the deployable attachment feature 2084 and thelip 2048 in the slot 2046 can prevent the deployable attachment feature2084 from returning to the undeployed position. In certain embodiments,the longitudinal portion 2086 of each deployable attachment feature 2084can be shorter than a narrow portion 2047 of the slot 2046. In suchembodiments, the longitudinal portion 2086 can be under tension when thelateral portion 2088 engages the lip 2048 in the slot 2046. The tensionin the lateral portion 2088 can hold the body 2082 of theanvil-attachable layer 2080 snugly against the anvil 2042.

The body 2082 and the deployable attachment features 2084 may be formedfrom a unitary body. Then, the apertures 2085 can be formed in the body2082 by, for example, cutting the apertures 2085 into the body 2082. Theapertures 2085 can be cut by a stamping tool, a cutting blade, a laser,or any other suitable means. In various other embodiments, theanvil-attachable layer 2080 and the apertures 2085 can be formed in amold. In certain embodiments, the apertures 2085 can include a gapbetween the body 2082 and a deployable attachment feature 2084. Incertain other embodiments, the apertures 2085 do not provide for a gapbetween the body 2082 and the deployable attachment features 2084. Invarious embodiments, the hinge 2087 can be formed by thinning or scoringthe anvil-attachable layer 2080 between the body 2082 and thelongitudinal portion 2086, for example. In various other embodiments,the hinges provide no change in thickness between the body 2082 and thelongitudinal portions 2086 of the deployable attachment features 2084.

FIGS. 238-240, described above, illustrate an embodiment of ananvil-attachable layer 2080 wherein the deployable attachment features2084 each include a lateral portion 2088 that includes a circularportion. The lateral portion can include other suitable shapes,including but not limited to triangles, ovals, and polygons. Forexample, FIGS. 241-243 illustrate an embodiment of an anvil-attachablelayer 2090 wherein the deployable attachment features 2094 each includea lateral portion 2098 that has a rectangular cross-section. Eachdeployable attachment feature 2094 can be attached to the body 2092 by ahinge 2097.

In certain embodiments, the body and deployable attachment features ofan anvil-attachable layer can comprise a flexible and/or a resilientmaterial. For example, referring again to FIGS. 238-240, the body 2082and deployable attachment features 2084 of anvil-attachable layer 2080can comprise a flexible and/or a resilient material. As another example,referring to FIGS. 241-243, the body 2092 and deployable attachmentfeatures 2094 of anvil-attachable layer 2090 can comprise a flexibleand/or a resilient material. Referring to the anvil-attachable layer2080 of FIGS. 238-240, when each deployable attachment feature 2084 isdeployed into a slot 2046, such as a knife slot, of an anvil 2042, thelateral portion 2088 can flex and/or deform to pass through a narrowportion 2047 of the slot 2046. Then, as the lateral portion 2088 extendspast the lips 2048 of the slot 2046 and into to a wide portion 2049 ofthe slot 2046, the lateral portion 2088 can return to an unflexed and/orundeformed shape. As the lateral portion 2088 returns to the unflexedand/or undeformed shape, the lateral portion 2088 can extend laterallyinto the wide portion 2049 of the slot 2046. After the lateral portion2088 extends laterally into the wide portion 2049 of the slot 2046, thenarrow portion 2047 of the slot 2046 can provide an interference fitthat inhibits the lateral portion 2088 from being readily pulled out ofthe slot 2046. Stated differently, to be pulled out of the slot 2046,the lateral portion 2088 must flex and/or deform again to fit throughthe narrow portion 2047 of the slot 2046. In various embodiments, thelateral portion 2088 and/or the narrow portion 2047 of the slot 2046 canbe sized so that a pulling force required to pull the deployableattachment feature 2084 out of the slot can be large enough so that theanvil-attachable layer 2080 is not displaced from the anvil 2042 whilethe anvil 2042 is positioned relative to patient tissue. However, thepulling force can be small enough such that the anvil-attachable layer2080 can pull away from the anvil after the anvil-attachable layer 2080is captured by staples.

In various embodiments, a cutting blade of a surgical stapler can severthe deployable attachment features of an anvil-attachable layer.Referring to FIG. 240, a cutting blade can travel through the slot 2046of the anvil 2042. The cutting blade can cut each deployable attachmentfeature 2084 substantially in half. The halves of each deployableattachment features 2084 can be easily pulled out of the slot 2046 whenthe anvil-attachable layer 2080 is removed from the anvil 2042 after thestaples are fired.

For anvil-attachable layers that include deployable attachment features,such as the anvil-attachable layers disclosed in FIGS. 238-243, aretainer can be used to align the anvil-attachable layer with an anviland to deploy the deployable attachment features into a slot in theanvil. FIGS. 251-254 illustrate a retainer 19700 that first installs astaple cartridge 19690 into a staple cartridge channel 19740 and thenpresses an anvil-attachable layer 2056 against an anvil 19720. Theretainer 19700 includes a first portion 2052 and a second portion 2054,wherein the first portion 2052 is movable relative to the second portion2054 in the directions indicated by arrows Q and S (shown in FIGS. 253and 254, respectively). The first portion 2052 can include a cam thatincludes anti-lobes 19646 and 19647 and lobes 19642 and 19643. Thesecond portion can include cam protrusions 19614 and 19616 that engagethe cam of the first portion 2052. As illustrated in FIGS. 251 and 252,when the retainer 19700 is being inserted into the end effector, the camprotrusions 19614 and 19616 engage the anti-lobes 16646 and 16647 of thecam of the first portion 2052. Referring now to FIGS. 253 and 254, afterthe staple cartridge has been seated in a staple cartridge channel 19740of the end effector, the first portion 2052 can move in the direction ofarrow Q relative to the second portion 2054. Moving the first portion2052 in the direction of arrow Q causes the cam protrusions 19614 and19616 to engage the lobes 19642 and 19643 of the cam of the firstportion 2052. The lobes 19642 and 19643 push the cam protrusions 19614and 19616 apart, thereby pushing the anvil-attachable layer 2056 intocontact with the anvil 19720.

Referring now to FIGS. 255-258, in certain embodiments, a retainer caninstall a staple cartridge in a staple cartridge channel, arrange ananvil-attachable layer on an anvil, and deploy deployable attachmentfeatures of the anvil-attachable layer into engagement with the anvil.Referring to FIGS. 256 and 257, embodiments of a retainer 2110 caninclude a grip portion 2112, a staple-cartridge-facing portion 2114, andan anvil-facing portion 2118. The staple-cartridge-facing portion 2114and the anvil-facing portion 2118 can be spaced apart and arranged at anangle relative to one another by a support 2116. As can best be seen inFIG. 258, the staple-cartridge-facing portion 2114 and the anvil-facingportion 2118 can be arranged at an angle similar to the angle betweenthe staple cartridge channel 2160 and the anvil 2150 when the anvil 2150is in a fully-open position. The staple-cartridge-facing portion 2114can include first clips 2124 and second clips 2126 extending therefrom.The first clips 2114 can engage and releasably hold a staple cartridge2140 to the retainer 2110, as illustrated in FIG. 255. The second clips2126 can engage a staple cartridge channel 2160 of an end effector, suchthat the retainer 2110 is releasably held to the staple cartridgechannel 2160. The anvil-facing portion 2118 can include a clip 2120 thatholds an anvil-attachable layer, such as the anvil-attachable layer 2080illustrated in FIGS. 238-240, relative to the anvil surface 2118. Theanvil-facing portion 2118 can also include discrete protrusions 2122that are positioned relative to locations of the deployable attachmentfeatures 2084 of the anvil-attachable layer 2080. As illustrated in FIG.255, when the anvil-attachable layer 2080 is loaded onto theanvil-facing portion 2118 of the retainer 2110, the anvil-attachablelayer 2080 can rest on top of the discrete protrusions 2122.

Referring to FIG. 258, in certain embodiments, as the retainer 2110 isbeing inserted into the end effector and the staple cartridge 2140 isbeing seated in the staple cartridge channel 2160, the anvil-attachablelayer 2080 can make contact with the anvil 2150. Once theanvil-attachable layer 2080 is in contact with the anvil 2150, theretainer 2110 and staple cartridge 2140 can continue to move relative tothe anvil 2150 until the staple cartridge 2140 is fully seated. In suchembodiments, the anvil-facing portion 2118 of the retainer 2110 can bemoved toward and be pushed against the anvil-attachable layer 2080 suchthat the discrete protrusions 2122 extending from the anvil-facingportion 2118 of the retainer 2110 can push the deployable attachmentfeatures 2084 in the layer 2080 into a deployed configuration, describedabove in connection with FIGS. 238-243. In various embodiments, eachdiscrete protrusion 2122 of the anvil-facing portion 2118 of theretainer 2110 can include an angled face 2123 that can engage thedeployable attachment features 2084. As the retainer 2110 continues tobe moved relative to the anvil 2150 and the anvil-attachable later 2080,the angled surfaces 2123 can be progressively engaged with thedeployable attachment features 2084 until the deployable attachmentfeatures 2084 have rotated about the hinges 2087 and are deployed in theslot 2152 of the anvil 2150. As illustrated in FIG. 258, the angledsurface 2123 of the discrete protrusions 2122 can support both thelongitudinal portion 2086 and the lateral portion 2088 of eachdeployable attachment feature such that both the longitudinal portion2086 and the lateral portion 2088 deploy in to the slot 2152 of theanvil 2150.

In certain other embodiments, the retainer 2110 may completely seat thestaple cartridge 2140 in the staple cartridge channel 2160 without theanvil-attachable layer 2080 contacting the anvil 2150. In suchembodiments, after the staple cartridge 2140 is completely seated in thestaple cartridge channel 2160, the anvil 2150 can be moved from afully-open position toward a closed position so that the anvil 2150contacts the anvil-attachable layer 2080 and the discrete protrusions2122 deploy the deployable attachment features 2084 into the slot 2052of the anvil 2050.

FIGS. 259-262 illustrate another embodiment of a retainer 2170. Theretainer 2170 can include a staple-cartridge-facing portion 2174 and ananvil-facing portion 2178 spaced apart and arranged at an angle to oneanother by a support 2190. The staple-cartridge-facing portion 2174 canengage and releasably hold a staple cartridge 2140. Thestaple-cartridge-facing portion 2174 can also engage and releasably holda staple cartridge channel 2160 of an end effector. An anvil-attachablelayer, such as anvil-attachable layer 2080, described above withreference to FIGS. 238-240, can be arranged on the anvil-facing portion2178. As illustrated in greater detail in FIGS. 261 and 262, theanvil-facing portion 2178 can include apertures 2182 that can be alignedwith the deployable attachment features 2084 of the anvil-attachablelayer 2080 arranged on the anvil-facing portion 2178. Each aperture 2182can include a cam 2202 arranged therein. Each cam 2202 can be attachedto the anvil-facing portion 2178 by a flexible member 2204 such that thecam 2202 can rotate about the flexible member 2204 out of the aperture2182 and into contact with the deployable attachment feature 2084. Eachcam 2202 can include a curved surface 2203 that can progressively deploythe deployable attachment feature 2084 into a slot 2152 in the anvil2150. Referring to FIG. 261, as the cam begins to be moved out of theaperture 2182 and into contact with the deployable attachment feature2084, the curved surface 2203 of the cam 2202 will first make contactwith the lateral portion 2088 of the deployable attachment feature 2084such that the lateral portion 2088 is deployed into the slot 2152 of theanvil 2150. Now referring to FIG. 262, as the cam 2202 continues to bemoved out of the aperture 2182, the curved surface 2203 of the cam 2202can contact the longitudinal portion 2086 of the deployable attachmentfeature 2086 such that the lateral portion 2086 is also deployed intothe slot 2152 of the anvil 2150.

The support 2190 between the staple-cartridge-facing portion 2174 andthe anvil-facing portion 2178 can include a stationary portion 2194 anda moveable portion 2196. The moveable portion 2196 can be operablycoupled to a button 2192 that a user can push to move the moveableportion 2196 relative to the stationary portion 2194. The moveableportion 2196 of the support 2190 can include a series of cam surfaces2206 that can engage the cam portions 2202 to push the cam portions 2202out of the apertures 2182. When the moveable portion 2196 is movedproximally relative to the stationary portion 2194, the cam surfaces2206 can displace the cams 2202 out of the apertures 2182 and intocontact with the deployable attachment features 2084 of the film 2080,as described above.

In certain embodiments, the movable portion 2196 of the support 2190 canbe biased in a distal position relative to the stationary portion 2194,as illustrated in FIG. 259. For example, a spring or the like may bearranged between the stationary portion 2194 and the moveable portion2196. The spring can bias the movable portion 2196 of the support 2190in a distal position relative to the stationary portion 2194. In variousembodiments, the biasing force can be sufficiently high such that forcesrequired to seat the staple cartridge 2140 in the staple cartridgechannel 2160 will not overcome the biasing force. As a result, thedeployable attachment features 2084 are less likely to be deployed bythe cams 2202 if forces required to completely seat the staple cartridge2140 in the staple cartridge channel 2160 are inadvertently applied tothe button 2192.

In various embodiments in which an anvil-attachable layer is releasablyretained to an anvil of a surgical stapler, the anvil-attachable layercan include additional features to stabilize patient tissue relative tothe layer and to the anvil. Referring now to FIGS. 249 and 250,anvil-attachable layers 22320 a and 22320 b are illustrated in aposition between an anvil 22060 and patient tissue T. Embodiments of theanvil-attachable layers 22320 a and 22320 b can include protrusions 2078extending from the body on a side facing the patient tissue T. Theprotrusions 2078 can push into or pierce the tissue T, providing gripbetween the tissue T and the anvil-attachable layers 22320 a and 22320b. The grip can prevent the tissue from slipping relative to theanvil-attachable layers 22320 a and 22320 b.

In various embodiments, the retention features may be separated from theanvil-attachable layer after a surgical stapler in which the layer isinstalled has been fired. In such embodiments, the retention featurescan be attached to one or more tethers. The tethers can be attached tothe surgical stapler or to another object outside of the patient so thatthe retention features can be removed from the patient by pulling on thetethers after the stapler has been fired.

In various embodiments, the tissue thickness compensator may comprise apolymeric composition. The polymeric composition may comprise one ormore synthetic polymer and/or one or more non-synthetic polymer. Thesynthetic polymer may comprise a synthetic absorbable polymer and/or asynthetic non-absorbable polymer. In various embodiments, the polymericcomposition may comprise a biocompatible foam, for example. Thebiocompatible foam may comprise a porous, open cell foam and/or aporous, closed cell foam, for example. The biocompatible foam can have auniform pore morphology or may have a gradient pore morphology (i.e.small pores gradually increasing in size to large pores across thethickness of the foam in one direction). In various embodiments, thepolymeric composition may comprise one or more of a porous scaffold, aporous matrix, a gel matrix, a hydrogel matrix, a solution matrix, afilamentous matrix, a tubular matrix, a composite matrix, a membranousmatrix, a biostable polymer, and a biodegradable polymer, andcombinations thereof. For example, the tissue thickness compensator maycomprise a foam reinforced by a filamentous matrix or may comprise afoam having an additional hydrogel layer that expands in the presence ofbodily fluids to further provide the compression on the tissue. Invarious embodiments, a tissue thickness compensator could also becomprised of a coating on a material and/or a second or third layer thatexpands in the presence of bodily fluids to further provide thecompression on the tissue. Such a layer could be a hydrogel that couldbe a synthetic and/or naturally derived material and could be eitherbiodurable and/or biodegradable, for example. In certain embodiments, atissue thickness compensator could be reinforced with fibrous non-wovenmaterials or fibrous mesh type elements, for example, that can provideadditional flexibility, stiffness, and/or strength. In variousembodiments, a tissue thickness compensator that has a porous morphologywhich exhibits a gradient structure such as, for example, small pores onone surface and larger pores on the other surface. Such morphology couldbe more optimal for tissue in-growth or haemostatic behavior. Further,the gradient could be also compositional with a varying bio-absorptionprofile. A short term absorption profile may be preferred to addresshemostasis while a long term absorption profile may address bettertissue healing without leakages.

Examples of non-synthetic polymers include, but are not limited to,lypholized polysaccharide, glycoprotein, elastin, proteoglycan, gelatin,collagen, and oxidized regenerated cellulose (ORC). Examples ofsynthetic absorbable polymers include, but are not limited to,poly(lactic acid) (PLA), poly(L-lactic acid) (PLLA), polycaprolactone(PCL), polyglycolic acid (PGA), poly(trimethylene carbonate) (TMC),polyethylene terephthalate (PET), polyhydroxyalkanoate (PHA), acopolymer of glycolide and ε-caprolactone (PGCL), a copolymer ofglycolide and-trimethylene carbonate, poly(glycerol sebacate) (PGS),polydioxanone, poly(orthoesters), polyanhydrides, polysaccharides,poly(ester-amides), tyrosine-based polyarylates, tyrosine-basedpolyiminocarbonates, tyrosine-based polycarbonates,poly(D,L-lactide-urethane), poly(B-hydroxybutyrate),poly(ε-caprolactone), polyethyleneglycol (PEG),poly[bis(carboxylatophenoxy) phosphazene], poly(amino acids),pseudo-poly(amino acids), absorbable polyurethanes, and combinationsthereof.

In various embodiments, the polymeric composition may comprise fromapproximately 50% to approximately 90% by weight of the polymericcomposition of PLLA and approximately 50% to approximately 10% by weightof the polymeric composition of PCL, for example. In at least oneembodiment, the polymeric composition may comprise approximately 70% byweight of PLLA and approximately 30% by weight of PCL, for example. Invarious embodiments, the polymeric composition may comprise fromapproximately 55% to approximately 85% by weight of the polymericcomposition of PGA and 15% to 45% by weight of the polymeric compositionof PCL, for example. In at least one embodiment, the polymericcomposition may comprise approximately 65% by weight of PGA andapproximately 35% by weight of PCL, for example. In various embodiments,the polymeric composition may comprise from approximately 90% toapproximately 95% by weight of the polymeric composition of PGA andapproximately 5% to approximately 10% by weight of the polymericcomposition of PLA, for example.

In various embodiments, the synthetic absorbable polymer may comprise abioabsorbable, biocompatible elastomeric copolymer. Suitablebioabsorbable, biocompatible elastomeric copolymers include but are notlimited to copolymers of ε-caprolactone and glycolide (preferably havinga mole ratio of ε-caprolactone to glycolide of from about 30:70 to about70:30, preferably 35:65 to about 65:35, and more preferably 45:55 to35:65); elastomeric copolymers of ε-caprolactone and lactide, includingL-lactide, D-lactide blends thereof or lactic acid copolymers(preferably having a mole ratio of ε-caprolactone to lactide of fromabout 35:65 to about 65:35 and more preferably 45:55 to 30:70)elastomeric copolymers of p-dioxanone (1,4-dioxan-2-one) and lactideincluding L-lactide, D-lactide and lactic acid (preferably having a moleratio of p-dioxanone to lactide of from about 40:60 to about 60:40);elastomeric copolymers of ε-caprolactone and p-dioxanone (preferablyhaving a mole ratio of ε-caprolactone to p-dioxanone of from about 30:70to about 70:30); elastomeric copolymers of p-dioxanone and trimethylenecarbonate (preferably having a mole ratio of p-dioxanone to trimethylenecarbonate of from about 30:70 to about 70:30); elastomeric copolymers oftrimethylene carbonate and glycolide (preferably having a mole ratio oftrimethylene carbonate to glycolide of from about 30:70 to about 70:30);elastomeric copolymer of trimethylene carbonate and lactide includingL-lactide, D-lactide, blends thereof or lactic acid copolymers(preferably having a mole ratio of trimethylene carbonate to lactide offrom about 30:70 to about 70:30) and blends thereof. In one embodiment,the elastomeric copolymer is a copolymer of glycolide andε-caprolactone. In another embodiment, the elastomeric copolymer is acopolymer of lactide and ε-caprolactone.

The disclosures of U.S. Pat. No. 5,468,253, entitled ELASTOMERIC MEDICALDEVICE, which issued on Nov. 21, 1995, and U.S. Pat. No. 6,325,810,entitled FOAM BUTTRESS FOR STAPLING APPARATUS, which issued on Dec. 4,2001, are hereby incorporated by reference in their respectiveentireties.

In various embodiments, the synthetic absorbable polymer may compriseone or more of 90/10 poly(glycolide-L-lactide) copolymer, commerciallyavailable from Ethicon, Inc. under the trade designation VICRYL(polyglactic 910), polyglycolide, commercially available from AmericanCyanamid Co. under the trade designation DEXON, polydioxanone,commercially available from Ethicon, Inc. under the trade designationPDS, poly(glycolide-trimethylene carbonate) random block copolymer,commercially available from American Cyanamid Co. under the tradedesignation MAXON, 75/25 poly(glycolide-ε-caprolactone) copolymer(poliglecaprolactone 25), commercially available from Ethicon, Inc.under the trade designation MONOCRYL, for example.

Examples of synthetic non-absorbable polymers include, but are notlimited to, foamed polyurethane, polypropylene (PP), polyethylene (PE),polycarbonate, polyamides, such as nylon, polyvinylchloride (PVC),polymethylmetacrylate (PMMA), polystyrene (PS), polyester,polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE),polytrifluorochloroethylene (PTFCE), polyvinylfluoride (PVF),fluorinated ethylene propylene (FEP), polyacetal, polysulfone, andcombinations thereof. The synthetic non-absorbable polymers may include,but are not limited to, foamed elastomers and porous elastomers, suchas, for example, silicone, polyisoprene, and rubber. In variousembodiments, the synthetic polymers may comprise expandedpolytetrafluoroethylene (ePTFE), commercially available from W. L. Gore& Associates, Inc. under the trade designation GORE-TEX Soft TissuePatch and co-polyetherester urethane foam commercially available fromPolyganics under the trade designation NASOPORE.

The polymeric composition of a tissue thickness compensator may becharacterized by percent porosity, pore size, and/or hardness, forexample. In various embodiments, the polymeric composition may have apercent porosity from approximately 30% by volume to approximately 99%by volume, for example. In certain embodiments, the polymericcomposition may have a percent porosity from approximately 60% by volumeto approximately 98% by volume, for example. In various embodiments, thepolymeric composition may have a percent porosity from approximately 85%by volume to approximately 97% by volume, for example. In at least oneembodiment, the polymeric composition may comprise approximately 70% byweight of PLLA and approximately 30% by weight of PCL, for example, andcan comprise approximately 90% porosity by volume, for example. In atleast one such embodiment, as a result, the polymeric composition wouldcomprise approximately 10% copolymer by volume. In at least oneembodiment, the polymeric composition may comprise approximately 65% byweight of PGA and approximately 35% by weight of PCL, for example, andcan have a percent porosity from approximately 93% by volume toapproximately 95% by volume, for example. In various embodiments, thepolymeric composition may comprise a greater than 85% porosity byvolume. The polymeric composition may have a pore size fromapproximately 5 micrometers to approximately 2000 micrometers, forexample. In various embodiments, the polymeric composition may have apore size between approximately 10 micrometers to approximately 100micrometers, for example. In at least one such embodiment, the polymericcomposition can comprise a copolymer of PGA and PCL, for example. Incertain embodiments, the polymeric composition may have a pore sizebetween approximately 100 micrometers to approximately 1000 micrometers,for example. In at least one such embodiment, the polymeric compositioncan comprise a copolymer of PLLA and PCL, for example. According tocertain aspects, the hardness of a polymeric composition may beexpressed in terms of the Shore Hardness, which can defined as theresistance to permanent indentation of a material as determined with adurometer, such as a Shore Durometer. In order to assess the durometervalue for a given material, a pressure is applied to the material with adurometer indenter foot in accordance with ASTM procedure D2240-00,entitled, “Standard Test Method for Rubber Property-Durometer Hardness”,the entirety of which is incorporated herein by reference. The durometerindenter foot may be applied to the material for a sufficient period oftime, such as 15 seconds, for example, wherein a reading is then takenfrom the appropriate scale. Depending on the type of scale being used, areading of 0 can be obtained when the indenter foot completelypenetrates the material, and a reading of 100 can be obtained when nopenetration into the material occurs. This reading is dimensionless. Invarious embodiments, the durometer may be determined in accordance withany suitable scale, such as Type A and/or Type OO scales, for example,in accordance with ASTM D2240-00. In various embodiments, the polymericcomposition of a tissue thickness compensator may have a Shore Ahardness value from approximately 4 A to approximately 16 A, forexample, which is approximately 45 OO to approximately 65 OO on theShore OO range. In at least one such embodiment, the polymericcomposition can comprise a PLLA/PCL copolymer or a PGA/PCL copolymer,for example. In various embodiments, the polymeric composition of atissue thickness compensator may have a Shore A Hardness value of lessthan 15 A. In various embodiments, the polymeric composition of a tissuethickness compensator may have a Shore A Hardness value of less than 10A. In various embodiments, the polymeric composition of a tissuethickness compensator may have a Shore A Hardness value of less than 5A. In certain embodiments, the polymeric material may have a Shore OOcomposition value from approximately 35 OO to approximately 75 OO, forexample.

In various embodiments, the polymeric composition may have at least twoof the above-identified properties. In various embodiments, thepolymeric composition may have at least three of the above-identifiedproperties. The polymeric composition may have a porosity from 85% to97% by volume, a pore size from 5 micrometers to 2000 micrometers, and aShore A hardness value from 4 A to 16 A and Shore OO hardness value from45 OO to 65 OO, for example. In at least one embodiment, the polymericcomposition may comprise 70% by weight of the polymeric composition ofPLLA and 30% by weight of the polymeric composition of PCL having aporosity of 90% by volume, a pore size from 100 micrometers to 1000micrometers, and a Shore A hardness value from 4 A to 16 A and Shore OOhardness value from 45 OO to 65 OO, for example. In at least oneembodiment, the polymeric composition may comprise 65% by weight of thepolymeric composition of PGA and 35% by weight of the polymericcomposition of PCL having a porosity from 93% to 95% by volume, a poresize from 10 micrometers to 100 micrometers, and a Shore A hardnessvalue from 4 A to 16 A and Shore OO hardness value from 45 OO to 65 OO,for example.

In various embodiments, a tissue thickness compensator may be releasablyattached to a staple cartridge and/or anvil by a flowable attachmentportion. The flowable attachment portion may be operatively associatedwith the staple cartridge and/or anvil. In various embodiments, aflowable attachment portion may be provided between the tissue thicknesscompensator and the staple cartridge and/or anvil. In variousembodiments, at least a portion of an outer surface of the tissuethickness compensator may comprise the flowable attachment portion. Invarious embodiments, an adhesive laminate may comprise the tissuethickness compensator and flowable attachment portion. The adhesivelaminate may comprise a base layer comprising the tissue thicknesscompensator and an adhesive layer on at least a portion of a surface ofthe base layer comprising the flowable attachment portion. The adhesivelaminate may comprise a tissue contacting surface comprising the tissuethickness compensator and an opposing surface comprising the flowableattachment portion. The adhesive laminate may releasably attach theadhesive laminate to a staple cartridge and/or anvil.

In various embodiments, a flowable attachment portion may comprise aflowable polymeric composition, such as a pressure sensitive adhesive(“PSA”), for example. An effective amount of the PSA may be applied tothe tissue thickness compensator to provide adequate cohesive strengthto produce the desired adhesion properties to the staple cartridgeand/or anvil. PSAs may be characterized by one or more of the followingproperties: (1) aggressive and permanent tack; (2) adherence with nomore than finger pressure; (3) sufficient ability to hold onto anadherend; and (4) sufficient cohesive strength to be removed cleanlyfrom the adherend. In various embodiments, the flowable attachmentportion may flow when pressure, heat, and/or stress are applied thereto.Such pressure and/or stress may be applied directly by hand and/or by adevice, such as, for example, a mechanical device, and may be a manualprocess and/or an automated process.

In various embodiments, the flowable attachment portion may beresponsive to a temperature change and/or a pressure change. In variousembodiments, the flowable attachment portion may flow from a firstposition to a second position when heat and/or pressure are appliedthereto. In various embodiments, the flowable attachment portion may beflowable at body temperature (37° C.) and/or room temperature (25° C.).In various embodiments, the flowable attachment portion may be flowableat body temperature (37° C.) but not at room temperature (25° C.). Invarious embodiments, the flowable attachment portion may be responsiveto a temperature change such that the flowable attachment portion is inthe first position when the tissue thickness compensator is at a firsttemperature and in the second position when the tissue thicknesscompensator is at a second temperature. In various embodiments, thesecond temperature may be greater than the first temperature. In variousembodiments, the first temperature may be room temperature and thesecond temperature may be body temperature. In various embodiments, theflowable attachment portion may be responsive to a pressure change suchthat the flowable attachment portion is in the first position when thetissue thickness compensator is at a first pressure and in the secondposition when the tissue thickness compensator at a second pressure. Invarious embodiments, the second pressure may be greater than the firstpressure. In various embodiments, the first pressure may be atmosphericpressure and the second pressure may be finger pressure. In variousembodiments, the flowable attachment portion may flow from a firstposition when at room temperature and/or atmospheric pressure to asecond position when at body temperature and/or under pressure. Invarious embodiments, the flowable attachment portion may flow from afirst (unstressed) position to the second position when pressure and/orstress are applied thereto.

In various embodiments, the flowable attachment portion may flow into avoid in the staple cartridge and/or anvil. In various embodiments, theflowable attachment portion may flow when heat and/or pressure areapplied thereto and extend over at least a portion of the surface of thestaple cartridge and/or anvil lacking the flowable attachment portionand/or fill at least a portion of a void in the staple cartridge and/oranvil, such as, for example, a slot and/or a staple cavity. In variousembodiments, the flowable attachment portion may flow in-vivo to fill atleast a portion of a void in the staple cartridge and/or anvil. Invarious embodiments, the flowable attachment portion may flow such thatthe flowable attachment portion comprises a complementary shape to theat least a portion of the void in the staple cartridge and/or anvil. Invarious embodiments, the flowable polymeric composition may flow to fillat least a portion of a slot and/or staple cavity in the anvil. Invarious embodiments, the flowable attachment portion may flow into thevoid when pressure is applied thereto and take the shape of the void.Without wishing to be bound to any particular theory, it is believedthat the filling at least a portion of a void in the staple cartridgeand/or anvil with the flowable attachment portion may improve theattachment of the tissue thickness compensator to the staple cartridgeand/or anvil.

In various embodiments, a flowable attachment portion, such as, forexample, the PSA, may be responsive to a change in temperature and/or achange in pressure to move between a first position and/or a firstprofile and a second position and/or a second profile. In variousembodiments, the flowable attachment portion may have a first positionspaced away from the staple cartridge and/or anvil. In variousembodiments, the flowable attachment portion may be configured topenetrate a void in the staple cartridge and/or anvil and/or fill atleast a portion of the void in the staple cartridge and/or anvil whenthe flowable attachment portion is in the second position. As describedherein, the flowable attachment portion may take the shape of the voidsuch that the flowable attachment portion comprises a profilecomplementary to the void when the flowable attachment portion is in thesecond profile. In various embodiments, the first position and/or firstprofile may be spaced from the staple cartridge and/or anvil, and thesecond position and/or second profile may contact the staple cartridgeand/or anvil. In various embodiments, the first position and/or firstprofile may comprise a neutral (original) profile when at roomtemperature and/or atmospheric pressure and the second position and/orsecond profile may comprise a complementary profile to the void in thestaple cartridge and/or anvil when at body temperature and/or underpressure. The profile of the flowable attachment portion may flow toachieve a complementary shape and/or dimension of the void in the staplecartridge and/or anvil.

In various embodiments, a method of bonding a tissue thicknesscompensator to a substrate, such as, for example, a staple cartridgeand/or an anvil, may generally comprise providing a tissue thicknesscompensator; applying a flowable attachment portion, such as a pressuresensitive adhesive, for example, to at least a portion of a surface ofthe tissue thickness compensator; and contacting the flowable attachmentportion and the substrate. In various embodiments, the method of bondinga tissue thickness compensator to a substrate may comprise applyingpressure to at least one of the tissue thickness compensator andsubstrate. The flowable attachment portion may flow from a firstposition on an outer surface of the tissue thickness compensator to asecond position further comprising an outer surface and/or inner surfaceof the substrate. The flowable attachment portion may come into contactwith the substrate causing adhesion of the tissue thickness compensatorto the substrate. In various embodiments, the flowable attachmentportion may bond the tissue thickness compensator to the substrate. Invarious embodiments, the flowable attachment portion may flow into atleast one void in the substrate, such as, for example, a slot and/orstaple cavity. In various embodiments, the flowable attachment portionmay fill at least a portion of the at least one void in the substratewhen in the second position.

In various embodiments, a method of attaching a tissue thicknesscompensator to a substrate, such as, for example, a staple cartridgeand/or an anvil, may generally comprise applying at least one discretebead and/or strip of a flowable polymeric composition, such as apressure sensitive adhesive, for example, to a surface of the tissuethickness compensator; contacting the substrate and the at least onediscrete bead and/or strip of the flowable polymeric composition; andpressing one of the substrate and at least one discrete bead and/orstrip of flowable polymeric composition into the other of the substrateand at least one discrete bead and/or strip of flowable polymericcomposition to releasably attach the tissue thickness compensator to thesubstrate. In various embodiments, the method of attaching a tissuethickness compensator to a substrate may comprise applying the at leastone discrete bead and/or strip of flowable polymeric composition to thesubstrate at a perimeter and/or central axis of the tissue thicknesscompensator at an expected location of the substrate. In variousembodiments, the method of attaching a tissue thickness compensator to asubstrate may comprise applying the at least one discrete bead and/orstrip of flowable polymeric composition in a longitudinal directionand/or lateral direction on the tissue thickness compensator.

In various embodiments, the method of attaching a tissue thicknesscompensator to a substrate may comprise applying the at least onediscrete bead and/or strip of flowable polymeric composition in apattern and/or an amount that is preselected based at least in part onexpected loads on the tissue thickness compensator. The patterns andamount of the flowable polymeric composition to be applied may beselected to withstand the stresses, e.g., shear stress, associated witha clinician's manipulation of the medical device. The patterns andamount of the flowable polymeric composition to be applied may bepreferably selected to balance loads on the flowable polymericcomposition due to the clinician's manipulation with ease of applicationand/or conservation of the flowable polymeric composition. In addition,the composition of the flowable polymeric composition may be consideredwhen selecting the patterns and amount of the flowable polymericcomposition to apply.

In various embodiments, the flowable attachment portion may partiallyadhere the tissue thickness compensator to the staple cartridge and/oranvil and/or fully partially adhere the tissue thickness compensator tothe staple cartridge and/or anvil. A fully adhered tissue thicknesscompensator may include a full layer of the flowable polymericcomposition, such as, for example, a pressure sensitive adhesive,between the tissue thickness compensator and the substrate. A fullyadhered tissue thickness compensator may lack a portion of the tissuethickness compensator free of the flowable polymeric composition. Apartially adhered tissue thickness compensator may include an effectiveamount of the flowable polymeric composition between the tissuethickness compensator and substrate that includes at least a portion ofthe tissue thickness compensator free of the flowable polymericcomposition. A partially adhered tissue thickness compensator may exerta greater shear stress on the flowable polymeric composition relative toa fully adhered tissue thickness compensator. Therefore, the shearproperties of the flowable polymeric composition and/or the amount andpatterns of the flowable polymeric composition may be selected towithstand the expected manipulation of the medical device by theclinician.

In various embodiments, the flowable polymeric composition may beapplied to the tissue thickness compensator in one of a continuouspattern and a discontinuous pattern. In various embodiments, acontinuous pattern of flowable polymeric composition may comprise adiscrete strip of flowable polymeric composition applied to at least aportion of the tissue thickness compensator. In various embodiments, acontinuous pattern of flowable polymeric composition may comprise acontinuous bead of flowable polymeric composition disposed along atleast a portion of the central axis of the tissue thickness compensatorin the longitudinal direction and/or at least a portion of a perimeterof the tissue thickness compensator. The flowable polymeric compositionmay be applied in various other patterns and configurations on thesubstrate, such as, for example, a crisscrossed pattern or otherdiagonal patterns, in a continuous full sheet or layer, or in any otherdesign to achieve the desired adhesive properties. In variousembodiments, the continuous pattern of flowable polymeric compositionmay be applied along an inner periphery and/or outer periphery of thetissue thickness compensator. In various embodiments, the continuouspattern of flowable polymeric composition may be applied along an innerperiphery of the tissue thickness compensator to be positioned along acentral longitudinal axis of the substrate when attached thereto. Invarious embodiments, the continuous pattern of flowable polymericcomposition may be applied along an inner periphery of the tissuethickness compensator to be aligned with at least one void in thesubstrate, such as a slot and/or staple cavity, for example, whenattached thereto. In various embodiments, the continuous pattern offlowable polymeric composition may be applied along an outer peripheryof the tissue thickness compensator to be positioned along an outerperimeter of the substrate when attached thereto. In variousembodiments, the flowable polymeric composition may be applied to thetissue thickness compensator to leave an inner portion and/or aperipheral border on the substrate that is free of flowable polymericcomposition.

In various embodiments, a discontinuous pattern of flowable polymericcomposition may comprise a plurality of discrete beads and/or strips offlowable polymeric composition spaced apart from each other on thesubstrate. In various embodiments, at least a portion of the pluralityof beads and/or strips of flowable polymeric composition may becompressed together when pressure and/or stress is applied. In variousembodiments, the compressed plurality of beads and/or strips of flowablepolymeric composition may form a continuous pattern of flowablepolymeric composition. In various embodiments, a partially adheredtissue thickness compensator may comprise a plurality of discrete beadsand/or strips of flowable polymeric composition on a surface of thetissue thickness compensator spaced apart from each other such that atleast a portion of the tissue thickness compensator comprises free spacelacking the flowable polymeric composition when pressure is applied. Thefree space may comprise a portion of the tissue thickness compensator inwhich the beads and/or strips of flowable polymeric composition do notcontact each other and/or a portion of the tissue thickness compensatorin which the beads and/or strips of flowable polymeric composition arenot applied. In various embodiments, the free space may comprise aninner portion and/or a peripheral border on the substrate.

In various embodiments, the method of attaching the tissue thicknesscompensator to the substrate may comprise applying at least one discretestrip of flowable polymeric composition to the tissue thicknesscompensator. In various embodiments, a discrete strip of flowablepolymeric composition may extend along a portion of the centrallongitudinal axis of the tissue thickness compensator. In at least oneembodiment, a discrete strip of flowable polymeric composition may beapplied along a portion of the tissue thickness compensator aligned withat least one void in the substrate, such as a slot and/or staple cavity.In various embodiments, the method of attaching the tissue thicknesscompensator to the substrate may comprise applying a plurality ofparallel discrete strips of flowable polymeric composition to the tissuethickness compensator. In various embodiments, two discrete strips offlowable polymeric composition may extend in the longitudinal directionalong opposing side edges of the tissue thickness compensator. In atleast one embodiment, each of the two discrete strips of flowablepolymeric composition may applied along a portion of the tissuethickness compensator aligned with at least one void in the substrate,such as a slot and/or staple cavities, for example. In variousembodiments, the distance between the strips and/or side edge may bepreselected such that the flowable polymeric composition may flow intoat least one void in the substrate, such as, for example, at least onestaple cavity in an anvil, when attached thereto.

In various embodiments, the distance between the plurality of paralleldiscrete strips of flowable polymeric composition and/or side edge maybe preselected to one of fully adhere the tissue thickness compensatorto the substrate and partially adhere the tissue thickness compensatorto the substrate. In various embodiments, a width of the strip may be atleast 1 mm, for example. In various embodiments, a width of the stripmay be between approximately 0.5 mm and approximately 1.5 mm, forexample. In various embodiments, a width of the strip may be betweenapproximately 1.0 mm and approximately 1.25 mm, for example. In variousembodiments, a width of a gap between the adhesive strips and/or sideedge may be at least 1 mm, for example. In various embodiments, thedistance between the strips and/or side edge may be preselected topartially adhere the tissue thickness compensator to the substrate withan adhesive to empty space ratio preselected based on expected loads onthe tissue thickness compensator. In various embodiments, the adhesiveto empty space ratio may be 1:10 to 10:1, such as, for example, 1:1,1:2, 1:3, 1:4, 1:5, and 2:3

In various embodiments, a minimum of 0.25 mm of the PSA substrate may beneeded to be flowable, for example. In various embodiments, the PSAsubstrate can comprise a thickness between approximately 1.25 mm andapproximately 1.50 mm, for example. In certain embodiments, the PSAsubstrate can comprise a thickness between approximately 0.5 mm andapproximately 0.75 mm, for example.

As described herein, in various embodiments, the flowable attachmentportion may comprise a flowable polymeric composition. The flowablepolymeric composition may comprise a pressure sensitive adhesive. Theflowable attachment portion may comprise a pressure sensitive adhesivelaminate. In various embodiments, the flowable attachment portion maycomprise an adhesive laminate comprising the tissue thicknesscompensator and flowable polymeric composition. The polymericcomposition may comprise one or more synthetic polymers and/or one ormore natural polymers. The polymeric composition may be bioabsorbable,biocompatible and/or biodegradable. Examples of natural polymersinclude, but are not limited to, lypholized polysaccharide,glycoprotein, elastin, proteoglycan, gelatin, collagen, fibrin,fibronectin, fibrinogen, elastin, serum albumin, hemoglobin, ovalbumin,and oxidized regenerated cellulose (ORC) and combinations thereof.Examples of polysaccharides include, but are not limited to, hyaluronicacid, chondroitin sulfate, hydroxyethyl starch, hydroxyethyl cellulose,hydroxypropylcellulose, carboxyetyl-cellulose, chitan/chitosan, agaroseand alginate, and combinations thereof. Examples of synthetic polymersinclude, but are not limited to, poly(lactic acid) (PLA), poly(L-lacticacid) (PLLA), polycaprolactone (PCL), polyglycolic acid (PGA), poly(glycolic acid) poly (hydroxybutyrate), poly (phosphazine), polyester,poly(trimethylene carbonate) (TMC), polyethylene terephthalate (PET),polyhydroxyalkanoate (PHA), a copolymer of glycolide and ε-caprolactone(PGCL), a copolymer of glycolide and-trimethylene carbonate,poly(glycerol sebacate) (PGS), polydioxanone, poly(orthoesters),polyanhydrides, polyacrylamides, polysaccharides, poly(ester-amides),tyrosine-based polyarylates, tyrosine-based polyiminocarbonates,tyrosine-based polycarbonates, poly(D,L-lactide-urethane),poly(B-hydroxybutyrate), poly(ε-caprolactone), polyethyleneglycol (PEG),polyethylene oxide, poly[bis(carboxylatophenoxy) phosphazene],poly(amino acids), pseudo-poly(amino acids), absorbable polyurethanes,polyhydroxyethylmethylacrylate, poly-vinylpyrrolidone, polyvinylalcohol, polyacrylic acid, polyacetate, polycaprolactone, polypropelene,nylon and combinations thereof.

In various embodiments, the flowable polymeric composition may comprisea copolymer of ε-caprolactone and glycolide (PCL/PGA). In variousembodiments, the flowable polymeric composition may comprise from about50% to about 90% by weight of the polymeric composition of PGA and about50% to about 10% by weight of the polymeric composition of PCL, forexample. In various embodiments, the flowable polymeric composition maycomprise from about 50% to about 75% by weight of the polymericcomposition of PGA and about 50% to about 25% by weight of the polymericcomposition of PCL, for example. In various embodiments, the flowablepolymeric composition may comprise from about 50% to about 60% by weightof the polymeric composition of PGA and about 50% to about 40% by weightof the polymeric composition of PCL, for example. In at least oneembodiment, the flowable polymeric composition may comprise about 70% byweight of polymeric composition of PGA and about 30% by weight of thepolymeric composition of PCL, for example. In at least one embodiment,the flowable polymeric composition may comprise about 64% by weight ofpolymeric composition of PGA and about 36% by weight of the polymericcomposition of PCL, for example.

In various embodiments, the flowable polymeric composition may comprisea copolymer of ε-caprolactone and lactide, including L-lactide,D-lactide blends thereof and lactic acid copolymers. In variousembodiments, the flowable polymeric composition may comprise a moleratio of PCL to PGA from 30:70 to 70:30, such as, for example, 35:65 to65:35, 45:55 to 35:65, and 50:50. In various embodiments, the amount ofε-caprolactone may be from 30 and 45 mole percent with the balance beingglycolide, such as, for example, 35 to 40 mole percent ε-caprolactonewith the balance being glycolide. In various embodiments, the PSA maycomprise a 36:64 (mol/mol) [poly(ε-caprolactone-co-glycolide)]copolymer. In various embodiments, the flowable polymeric compositionmay comprise a copolymer of p-dioxanone (1,4-dioxan-2-one) and lactide,including L-lactide, D-lactide and lactic acid. In various embodiments,the flowable polymeric composition may comprise a mole ratio ofp-dioxanone to lactide of from 40:60 to 60:40. In various embodiments,the flowable polymeric composition may comprise a copolymer ofε-caprolactone and p-dioxanone. In various embodiments, the flowablepolymeric composition may comprise a mole ratio of ε-caprolactone top-dioxanone of from 30:70 to 70:30.

In various embodiments, the tissue thickness compensator and flowableattachment portion may comprise one of a same polymeric composition anda different polymeric composition. In various embodiments, the tissuethickness compensator and flowable attachment portion may each comprisethe same bioabsorbable material, such as, for example, a copolymer ofε-caprolactone and glycolide (PCL/PGA). In various embodiments, thetissue thickness compensator and flowable attachment portion may differin at least one characteristic selected from composition, modulus,elongation, inherent viscosity, crystallinity, and bioabsorption. Invarious embodiments, the tissue thickness compensator and flowableattachment portion may comprise the same copolymer that differs in atleast one characteristic selected from composition, modulus, elongation,inherent viscosity, crystallinity, and bioabsorption. For example, thetissue thickness compensator and flowable attachment portion may eachcomprise a PCL/PGA copolymer that differs in the weight percent ofε-caprolactone and glycolide and/or mole ratio of ε-caprolactone toglycolide. In at least one embodiment, the tissue thickness compensatormay comprise about 50% by weight of polymeric composition of PGA andabout 50% by weight of the polymeric composition of PCL, and theflowable attachment portion may comprise about 64% by weight ofpolymeric composition of PGA and about 36% by weight of the polymericcomposition of PCL. In at least one embodiment, the tissue thicknesscompensator may comprise a PCUPGA copolymer having a mole ratio ofε-caprolactone to glycolide of 50:50 and the flowable attachment portionmay comprise a PCL/PGA copolymer having a mole ratio of ε-caprolactoneto glycolide of 36:64.

In various embodiments, a concentration of ε-caprolactone in thepressure sensitive adhesive and a concentration of ε-caprolactone in thetissue thickness compensator may differ by at least 1 weight percent byweight of the polymeric compositions, respectively. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by at least 5 weight percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by at least 10 weight percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by at least 15 weight percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by 1 to 15 weight percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by 10 to 15 weight percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by 14 weight percent. In various embodiments, aconcentration of ε-caprolactone in the pressure sensitive adhesive maydiffer from a concentration of ε-caprolactone in the tissue thicknesscompensator as described above such that a concentration ofε-caprolactone in the pressure sensitive adhesive may be one of greaterthan and less than a concentration of ε-caprolactone in the tissuethickness compensator.

In various embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by at least 1 weightpercent. In various embodiments, a concentration of polyglycolic acid inthe pressure sensitive adhesive and a concentration of polyglycolic acidin the tissue thickness compensator may differ by at least 5 weightpercent. In various embodiments, a concentration of polyglycolic acid inthe pressure sensitive adhesive and a concentration of polyglycolic acidin the tissue thickness compensator may differ by at least 10 weightpercent. In various embodiments, a concentration of polyglycolic acid inthe pressure sensitive adhesive and a concentration of polyglycolic acidin the tissue thickness compensator may differ by at least 15 weightpercent. In various embodiments, a concentration of polyglycolic acid inthe pressure sensitive adhesive and a concentration of polyglycolic acidin the tissue thickness compensator may differ by at least 20 weightpercent. In various embodiments, a concentration of polyglycolic acid inthe pressure sensitive adhesive and a concentration of polyglycolic acidin the tissue thickness compensator may differ by 1 to 20 weightpercent. In various embodiments, a concentration of polyglycolic acid inthe pressure sensitive adhesive and a concentration of polyglycolic acidin the tissue thickness compensator may differ by 15 to 20 weightpercent. In various embodiments, a concentration of polyglycolic acid inthe pressure sensitive adhesive and a concentration of polyglycolic acidin the tissue thickness compensator may differ by 16 weight percent. Invarious embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive may differ from a concentration ofpolyglycolic acid in the tissue thickness compensator as described abovesuch that a concentration of polyglycolic acid in the pressure sensitiveadhesive may be one of greater than and less than a concentration ofpolyglycolic acid in the tissue thickness compensator.

In various embodiments, a concentration of ε-caprolactone in thepressure sensitive adhesive and a concentration of ε-caprolactone in thetissue thickness compensator may differ by at least 1 mole percent. Invarious embodiments, a concentration of ε-caprolactone in the pressuresensitive adhesive and a concentration of ε-caprolactone in the tissuethickness compensator may differ by at least 5 mole percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by at least 10 mole percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by at least 15 mole percent. In variousembodiments, a concentration of ε-caprolactone in the pressure sensitiveadhesive and a concentration of ε-caprolactone in the tissue thicknesscompensator may differ by 1 to 15 mole percent. In various embodiments,a concentration of ε-caprolactone in the pressure sensitive adhesive anda concentration of ε-caprolactone in the tissue thickness compensatormay differ by 10 to 15 mole percent. In various embodiments, aconcentration of ε-caprolactone in the pressure sensitive adhesive and aconcentration of ε-caprolactone in the tissue thickness compensator maydiffer by 14 mole percent. In various embodiments, a concentration ofε-caprolactone in the pressure sensitive adhesive may differ from aconcentration of ε-caprolactone in the tissue thickness compensator asdescribed above such that a concentration of ε-caprolactone in thepressure sensitive adhesive may be one of greater than and less than aconcentration of ε-caprolactone in the tissue thickness compensator.

In various embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by at least 1 mole percent.In various embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by at least 5 mole percent.In various embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by at least 10 mole percent.In various embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by at least 15 mole percent.In various embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by at least 20 mole percent.In various embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by 1 to 20 mole percent. Invarious embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by 15 to 20 mole percent. Invarious embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive and a concentration of polyglycolic acid inthe tissue thickness compensator may differ by 16 mole percent. Invarious embodiments, a concentration of polyglycolic acid in thepressure sensitive adhesive may differ from a concentration ofpolyglycolic acid in the tissue thickness compensator as described abovesuch that a concentration of polyglycolic acid in the pressure sensitiveadhesive may be one of greater than and less than a concentration ofpolyglycolic acid in the tissue thickness compensator.

In various embodiments, the polymeric compositions may compriseadditional optional components to further improve the processability ofthe compositions and/or mechanical characteristics and othercharacteristics, such as tackiness, resistance to ageing by light,oxygen and heat, and visual appearance, for example. Such optionalcomponents may include other copolymers that can be included in thepolymeric composition to achieve a desired property, such as, forexample, to increase adhesion or compatibility with the substrate. Invarious embodiments, the additional optional components may include, butare not limited to, other polymers or copolymers, fillers,cross-linkers, tackifiers, plasticizers, pigments, dyes, antioxidants,colorants and stabilizers. In various embodiments, the polymericcomposition may comprise a tackifier included in a finite amount of atleast 0.1, at least 2, or at least 5 up to 10, 25, or 50 weight percent,based on the total weight of polymeric composition. In variousembodiments, the polymeric composition may comprise a plasticizerincluded in a finite amount of at least 0.1, at least 2, or at least 5up to 10, 25, or 50 weight percent, based on the total weight ofpolymeric composition.

In various embodiments, the flowable attachment portion may comprise aflowable (plastically deformable) polymeric composition. In variousembodiments, the flowable polymeric composition may normally tacky atroom temperature (e.g., 20° C. to 25° C.) and releasably adhere to avariety of substrates using only moderate pressure, such as fingerpressure, for example, to form the bond to attach to the substrate. Invarious embodiments, the flowable polymeric composition may be a solidup to 40° C., up to 45° C., up to 50° C., up to 55° C., and/or up to 60°C. In various embodiments, the flowable polymeric composition may meltwithout degradation at greater than 40° C., greater than 45° C., greaterthan 50° C., greater than 55° C., greater than 60° C., and/or greaterthan 120° C. In various embodiments, the flowable polymeric compositionmay melt without degradation up to 600° C., up to 500° C., up to 400°C., up to 300° C., up to 240° C., and/or up to 180° C. In variousembodiments, the flowable polymeric composition may melt withoutdegradation from 40.1° C. to 600° C., 120° C. to 240° C., and/or 180° C.

In various embodiments, the flowable polymeric composition may becharacterized by an inherent viscosity in a 0.1 g/dLhexafluoroisopropanol solution at 25° C. from 0.6 to 4.0 dL/g, 0.8 to3.2 g/dL, 1.0 to 2.4 g/dL, and/or 1.6 g/dL. In various embodiments, theflowable polymeric composition may not comprise a gel.

In various embodiments, the flowable polymeric composition may becharacterized by one or more of the following properties: a percentcrystallinity of less than about 25 percent, a percent crystallinity ofless than about 15 percent, and a percent crystallinity from 15 to 25percent; a percent elongation greater than about 200, a percentelongation greater than about 500, and a percent elongation from about200 to about 500; and a modulus less than about 40,000 psi, a modulusless than about 20,000 psi, and a modulus from about 20,000 to about40,000 psi.

In various embodiments, the flowable attachment portion may comprise oneof a strip, tape, roll of tape, sheet, and film attached to a surfaceand/or edge of the tissue thickness compensator. In various embodiments,the flowable attachment portion may comprise a pressure sensitive tapecomprising an adhesive and a backing. In various embodiments, thebacking may comprise one of a flexible backing material and aninflexible backing material. Examples of flexible backing materialsinclude, but are not limited to plastic films such as polypropylene,polyethylene, polyvinyl chloride, polyester (polyethyleneterephthalate), polycarbonate, polymethyl(meth)acrylate (PMMA),cellulose acetate, cellulose triacetate, and ethyl cellulose. Foambackings may be used. Examples of inflexible backing materials include,but are not limited to, metal, metalized polymeric film, indium tinoxide coated glass and polyester, PMMA plate, polycarbonate plate,glass, or ceramic sheet material. In various embodiments, the pressuresensitive tape may comprise a release liner. In various embodiments, thepressure sensitive tape may be applied by removing the release linerthereby exposing the adhesive.

In various embodiments, the flowable attachment portion may be appliedto the tissue thickness compensator using conventional coatingtechniques, such as, for example, roller coating, flow coating, dipcoating, spin coating, spray coating, knife coating, and die coating. Invarious embodiments, the flowable attachment portion may have an initialthickness from approximately 1.25 mm to approximately 1.50 mm, forexample. In some embodiments, the flowable attachment portion may havean initial thickness from approximately 0.5 mm to approximately 0.75 mm,for example. In various embodiments, the flowable attachment portion mayhave a final thickness of at least 0.25 mm, for example, when pressureis applied thereto.

In various embodiments, referring to FIG. 263, the flowable attachmentportion 30000 may comprise a continuous strip centrally disposed in alongitudinal direction along a portion of the central axis of the tissuethickness compensator 30010. The width of the strip may be at least 1mm, for example. The width of the strip can be between approximately 0.5mm and approximately 1.5 mm, for example. The width of the strip can bebetween approximately 1.0 mm and approximately 1.25 mm, for example. Thefirst position of the flowable attachment portion 30000 may be spacedaway from the anvil 30020 and the first profile of the flowableattachment portion 30000 may comprise a neutral (original) profile. Asshown in FIG. 264, the flowable attachment portion 30000 may be alignedwith a void 30025 in the anvil 30020, such as a centrally disposed slot,for example. As shown in FIG. 265, the flowable attachment portion 30000may flow into the slot 30025 and come into securing engagement with theanvil 30020 when a threshold level of pressure is applied to theflowable attachment portion 30000. The flowable attachment portion 30000may fill at least a portion of the slot 30025 such that the flowableattachment portion 30000 may take the shape of the slot 30025. Thesecond position of the flowable attachment portion 30000 may contact theanvil 30020 and the second profile of the flowable attachment 30000portion may comprise a complementary profile to the slot 30025. Theflowable attachment portion 30000 may releasably attach the tissuethickness compensator 30010 to the anvil 30020.

In various embodiments, referring to FIG. 266, the flowable attachmentportion 30000 may comprise two continuous strips parallel to each otherand disposed in a longitudinal direction along a portion of the tissuethickness compensator 30010. The width of the strip may be at least 1mm, for example. The width of the strip can be between approximately 0.5mm and approximately 1.5 mm, for example. The width of the strip can bebetween approximately 1.0 mm and approximately 1.25 mm, for example. Thetwo discrete strips may be spaced apart from the central axis and sideedges of the tissue thickness compensator 30010. The width of a gapbetween the each strip may be at least 1 mm, for example, and the widthof a gap between the each strip and side edge may be at least 1 mm, forexample. The adhesive to empty space ratio may be between approximately1:4 and approximately 1:2, for example. The adhesive to empty spaceratio may be at least 1:10, for example. In various circumstances, theadhesive to empty space ratio may be zero. A constant layer across theentire surface may be desirable, in some circumstances. The firstposition of the flowable attachment portion 30000 may be spaced awayfrom the anvil 30020 and the first profile of the flowable attachmentportion 30000 may comprise a neutral (original) profile. As shown inFIG. 267, the flowable attachment portion 30000 may be aligned with thestaple forming cavities 30030, for example. As shown in FIG. 268, theflowable attachment portion 30000 may flow into the staple cavities30030 and come into securing engagement with the anvil 30020 when athreshold level of pressure, such as finger pressure, for example, isapplied to the flowable attachment portion 30000. The flowableattachment portion 30000 may fill at least a portion of the staplecavity 30030 such that the flowable attachment portion 30000 may takethe shape of the staple cavity 30030. At least a portion of the staplecavities 30030 may be free of the flowable attachment portion 30000. Thesecond position of the flowable attachment portion 30000 may contact theanvil 30020 and the second profile of the flowable attachment portion30000 may comprise a complementary profile to the staple cavities 30030.The flowable attachment portion 30000 may releasably attach the tissuethickness compensator 30000 to the anvil 30020.

In various embodiments, referring now to FIGS. 269-273, a staplecartridge 30100 comprising a support portion 30102 and a tissuethickness compensator 30110 can be loaded into a staple cartridgechannel with a staple cartridge applicator 30140, for example. Invarious embodiments, an applicator 30140 can be configured to positionan upper tissue thickness compensator 30110 relative to an anvil 30120in addition to positioning a staple cartridge 30100 within a staplecartridge channel. The applicator 30140 can comprise latch arms 30141which can be releasably engaged with lock projections extending from asupport portion 30102 of the staple cartridge 30100 such that theapplicator 30140 can be maintained in position over a tissue thicknesscompensator 30110 of the staple cartridge 30100. In various embodiments,the upper tissue thickness compensator 30110 can be removably attachedto the applicator 30140 such that the anvil 30120 of a surgicalinstrument can be closed onto the applicator 30140, engage the tissuethickness compensator 30110, and detach from the tissue thicknesscompensator 30110 from the applicator 30140. In various embodiments, thetissue thickness compensator 30110 and/or the anvil 30120 can compriseone or more retention features which can be configured to releasablyhold the tissue thickness compensator 30110 to the anvil. In variousembodiments, the retention features may comprise an adhesive sheetand/or an adhesive tab 30112.

In various embodiments, the adhesive sheet and/or an adhesive tab may beintegrally formed from a portion of the tissue thickness compensator30110. In various embodiments, the tissue thickness compensator 30110may comprise at least one adhesive tab 30112 along an edge of the tissuethickness compensator 30110. The adhesive tab 30112 may comprise arelease liner 30113. Referring to FIG. 271, the anvil 30120 may be movedto a closed position to engage the tissue thickness compensator 30110.The release liner 30113 may be removed to expose an adhesive surface ofthe adhesive tab 30112. Referring to FIGS. 272 and 273, a first end ofthe adhesive tab 30112 may be secured to the anvil and a second end ofthe adhesive tab 30112 may be secured to the anvil to releasably attachthe tissue thickness compensator 30110 to the anvil. The adhesive tab30112 may be pulled distally to detach the tissue thickness compensator30110 from the applicator 30140. Thereafter, the anvil and the staplecartridge 30100 can be positioned relative to the tissue that is to bestapled and/or incised. The clinician may pull the adhesive tab 30112 todetach the tissue thickness compensator 30110 from the anvil.

Referring to FIGS. 284-288, in various embodiments, the tissue thicknesscompensator 30210 may comprise at least one adhesive tab 30212 along adistal edge of the tissue thickness compensator 30210. The adhesive tab30212 may comprise a release liner 30213. As described herein, a staplecartridge applicator 30240 can be configured to position an upper tissuethickness 30210 compensator relative to an anvil 30220. The releaseliner 30213 may be removed to expose an adhesive surface of the adhesivetab 30212. The adhesive tab 30212 may be folded over and secured to theanvil 30220 to releasably attach the tissue thickness compensator 30210to the anvil 30220. The adhesive tab 30212 may be pulled distally todetach the tissue thickness compensator 30210 from the applicator 30240.Thereafter, the anvil 30220 and the staple cartridge 30200 can bepositioned relative to the tissue that is to be stapled and/or incised.Referring to FIGS. 289-290, in use, a staple-deploying sled can beadvanced distally through the staple cartridge by a firing member thatcan advance a knife edge 30211 through the tissue thickness compensator30210 in order to incise at least a portion of the adhesive tab 30212and progressively detach the tissue thickness compensator 30210 from theanvil 30220. The clinician may pull the remainder of the adhesive tab30212 from the anvil 30220 before reloading a new staple cartridge30200.

In various embodiments, the adhesive sheet and/or an adhesive tab may beseparate from the tissue thickness compensator. Referring to FIGS.274-276, in at least one embodiment, an adhesive tab 30312 (see alsoFIGS. 288 and 292) may be provided between the staple cartridge 30300and tissue thickness compensator 30310. The tissue thickness compensator30310 may comprise a notch 30311 configured and dimensioned coordinatewith the adhesive tab 30312 to releasably retain the tissue thicknesscompensator 30310 to the anvil 30320. A first end of the adhesive tab30312 may be secured to the tissue thickness compensator 30310 adjacentthe notch 30311 and a second end of the adhesive tab 30312 may besecured to the anvil 30320. As shown in FIG. 277, the adhesive tab 30312is not engaging the notch 30311. Thereafter, the anvil 30320 and thestaple cartridge 30300 can be positioned relative to the tissue T thatis to be stapled and/or incised.

As described above, in use, a staple-deploying sled can be advanceddistally through the staple cartridge by a firing member in order toeject the staples from the staple cartridge, as outlined above. As thestaples are deformed, each staple can capture a portion of the tissuethickness compensator against the top surface of the tissue. At the sametime, the firing member can advance a knife edge through the tissuethickness compensator 30310, wherein, in at least one embodiment, theknife edge can be advanced through the tissue thickness compensator30310 to move the tissue thickness compensator 30310 distally and alignthe adhesive tab 30312 and notch 30311, as shown in FIGS. 277-279, inorder to incise the tissue thickness compensator 30310 and detach thetissue thickness compensator 30310 from the anvil 30320. In variousembodiments, as the staples are moved from their unfired positions totheir fired positions by the staple drivers, as discussed above, thetissue thickness compensator 30310 lacking a notch may move downwardly,as shown in FIGS. 280 and 281, to disengage the adhesive tabs 30312 anddetach the tissue thickness compensator 30310 from the anvil 30320.After the staples have been deployed, the anvil 30320 can be re-openedand moved away from the implanted tissue thickness compensator 30310, asshown in FIG. 283. The reader will appreciate, upon comparing FIGS. 282and 283, that the tissue thickness compensator 30310 can be fastened tothe tissue T and incised by the cutting member, as discussed above.

In various embodiments, the flowable attachment portion may be appliedby removing the first release liner from the first adhesive tab therebyexposing the flowable attachment portion comprising a pressure sensitiveadhesive, for example. The first adhesive tab may be rolled down orotherwise pressed onto the outer surface of the substrate. Next, thesecond release liner may be removed from the second adhesive tab therebyexposing the PSA. The second adhesive tab may be pressed onto the outersurface of the substrate and/or first adhesive tab. Once the PSA hasbeen applied to the tissue thickness compensator, it is placed incontact with the staple cartridge and/or anvil. The PSA may secure thetissue thickness compensator to the substrate.

Various embodiments described herein are described in the context ofstaples removably stored within staple cartridges for use with surgicalstapling instruments. In some circumstances, staples can include wireswhich are deformed when they contact an anvil of the surgical stapler.Such wires can be comprised of metal, such as stainless steel, forexample, and/or any other suitable material. Such embodiments, and theteachings thereof, can be applied to embodiments which include fastenersremovably stored with fastener cartridges for use with any suitablefastening instrument.

Various embodiments described herein are described in the context oftissue thickness compensators attached to, and/or for use with, staplecartridges and/or fastener cartridges. Such tissue thicknesscompensators can be utilized to compensate for variations in tissuethickness from one end of a staple cartridge to another, or forvariations in tissue thickness captured within one staple, or fastener,as compared to another. Such tissue thickness compensators can also beutilized to compensate for variations in tissue thickness from one sideof a staple cartridge to another. Such embodiments, and the teachingsthereof, can be applied to embodiments which include a layer, or layers,of material attached to, and/or for use with, staple cartridges and/orfastener cartridges. A layer can include buttress material.

Various embodiments described herein are described in the context oflinear end effectors and/or linear fastener cartridges. Suchembodiments, and the teachings thereof, can be applied to non-linear endeffectors and/or non-linear fastener cartridges, such as, for example,circular and/or contoured end effectors. For example, various endeffectors, including non-linear end effectors, are disclosed in U.S.patent application Ser. No. 13/036,647, filed Feb. 28, 2011, entitledSURGICAL STAPLING INSTRUMENT, now U.S. Patent Application PublicationNo. 2011/0226837, which is hereby incorporated by reference in itsentirety. Additionally, U.S. patent application Ser. No. 12/893,461,filed Sep. 29, 2012, entitled STAPLE CARTRIDGE, now U.S. PatentApplication Publication No. 2012/0074198, is hereby incorporated byreference in its entirety. U.S. patent application Ser. No. 12/031,873,filed Feb. 15, 2008, entitled END EFFECTORS FOR A SURGICAL CUTTING ANDSTAPLING INSTRUMENT, now U.S. Pat. No. 7,980,443, is also herebyincorporated by reference in its entirety.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

What is claimed is:
 1. An end effector for a surgical stapler, said endeffector comprising: a first jaw member, wherein said first jaw memberincludes a proximal end and a distal end; a staple cartridge arrangedrelative to said first jaw member, wherein said staple cartridgecomprises a nose portion arranged relative to said distal end of saidfirst jaw member; a layer arranged relative to said staple cartridge,wherein said layer includes a body and a distal end portion extendingfrom said body, and wherein said distal end portion of said layer isreleasably engaged with said nose portion of said staple cartridge; acutting member arranged relative to said nose portion of said staplecartridge, wherein said cutting member is movable between a firstposition and a second position to cut said layer proximal to said distalend portion such that said body of said layer disengages from said noseportion; and a firing member configured to engage said cutting membersuch that said cutting member moves between said first position and saidsecond position.
 2. The end effector of claim 1, wherein said firingmember is movable between said proximal end of said first jaw member andsaid distal end of said first jaw member to move said cutting memberfrom said first position to said second position.
 3. The end effector ofclaim 1, wherein said nose portion of said staple cartridge comprises alip configured to retain said distal end portion of said layer, whereinsaid lip defines a gap, wherein said distal end portion of said layerdefines a layer thickness, and wherein said layer thickness is greaterthan said gap.
 4. The end effector of claim 1, wherein said nose portionof said staple cartridge comprises a post, and wherein said distal endportion of said layer defines an aperture that receives said post. 5.The end effector of claim 1, wherein said staple cartridge comprises aplurality of staple cavities, and wherein said end effector furthercomprises a plurality of staples positioned within said staple cavities.6. The end effector of claim 1, wherein said firing member comprises atleast one of a staple driver and a tissue-cutting knife.
 7. The endeffector of claim 1, wherein said staple cartridge defines a channeltherethrough, and wherein said channel is configured to receive saidfiring member.
 8. The end effector of claim 1, wherein said staplecartridge defines a cutting member cavity, wherein said cutting memberis positioned within said cutting member cavity when in said firstposition, and wherein said cutting member at least partially protrudesfrom said cutting member cavity when in said second position.
 9. Astaple cartridge for use in a surgical stapler, the surgical staplerincluding a first jaw member that has a proximal end and a distal end,the endoscopic surgical stapler including a firing member configured tomove along the first jaw member between the proximal end and the distalend, said staple cartridge comprising: a cartridge body, wherein saidcartridge body is configured to operably engage the first jaw member ofthe surgical stapler, wherein said cartridge body comprises a stapledeck and a nose portion, wherein said cartridge body defines a channeltherethrough, wherein said staple deck includes a slot in communicationwith said channel, and wherein said channel is configured to receive thefiring member of the surgical stapler when said cartridge body isengaged with the first jaw member of the surgical stapler; a layerarranged relative to said staple deck, wherein said layer includes abody and a distal end portion extending from said body, and wherein saiddistal end portion of said layer is releasably engaged with said noseportion of said staple cartridge; and a cutting member arranged relativeto said nose portion of said staple cartridge, wherein said cuttingmember is movable between a first position and a second position to cutsaid layer proximal to said distal end portion such that said body ofsaid layer disengages from said nose portion when the firing member ofthe surgical stapler moves between the proximal end of the first jawmember and the distal end of the first jaw member.
 10. The staplecartridge of claim 9, wherein said nose portion of said staple cartridgecomprises a lip configured to retain said distal end portion of saidlayer, wherein said lip defines a gap, wherein said distal end portionof said layer defines a layer thickness, and wherein said layerthickness is greater than said gap.
 11. The staple cartridge of claim 9,wherein said nose portion of said staple cartridge comprises a post, andwherein said distal end portion of said layer defines an aperture thatreceives said post.
 12. The staple cartridge of claim 9, wherein saidstaple cartridge comprises a plurality of staple cavities, and whereinsaid staple cartridge further comprises a plurality of staplespositioned within said staple cavities.
 13. The staple cartridge ofclaim 9, wherein the firing member includes at least one of a stapledriver and a tissue-cutting knife.
 14. The staple cartridge of claim 9,wherein said staple cartridge defines a channel therethrough, andwherein said channel is configured to receive the firing member.
 15. Thestaple cartridge of claim 9, wherein said staple cartridge defines acutting member cavity, wherein said cutting member is positioned withinsaid cutting member cavity when in said first position, and wherein saidcutting member at least partially protrudes from said cutting membercavity when in said second position.
 16. A fastener cartridge,comprising: a cartridge body comprising a deck; a plurality of fastenersat least partially positioned within said cartridge body; a firingmember configured to be moved along a firing path to move each saidfastener between an unfired position and a fired position; a layerpositioned over said deck; and a cutting member movable between a firstposition and a second position in a transverse direction to cut saidlayer, wherein said transverse direction is transverse to said firingpath.
 17. The fastener cartridge of claim 16 wherein said firing memberis configured to move said cutting member between said first positionand said second position.
 18. The fastener cartridge of claim 17,wherein said firing path defines a first end and a second end, whereinsaid firing path begins at said first end and ends at said second end,and wherein said cutting member is positioned at said second end. 19.The fastener cartridge of claim 16, wherein said layer comprises atissue thickness compensator mounted to said cartridge body at saidsecond end.
 20. The fastener cartridge of claim 16, wherein saidtransverse direction is perpendicular to said firing path.
 21. Afastener cartridge, comprising: a cartridge body comprising a deck; aplurality of fasteners at least partially positioned within saidcartridge body; a compressible layer positioned over said deck, whereineach said fastener is deployable between an unfired configuration and afired configuration to capture at least a portion of said compressiblelayer therein, and wherein said compressible layer comprises a mountportion mounted to said cartridge body; a first cutting memberconfigured to transect said compressible layer along a firing path whichat least partially extends in a first direction; and a second cuttingmember configured to transect said compressible layer in a seconddirection along a detachment path, wherein said second direction isdifferent than said first direction.
 22. A fastener cartridge,comprising: a cartridge body, comprising: a proximal end; a distal end;and a deck positioned intermediate said proximal end and said distalend; a plurality of fasteners at least partially positioned within saidcartridge body; a compressible layer positioned over said deck, whereineach said fastener is deployable between an unfired configuration and afired configuration to capture at least a portion of said compressiblelayer therein, and wherein said compressible layer comprises a mountportion mounted to said cartridge body; a firing sled movable from saidproximal end toward said distal end to move said fasteners between saidunfired configuration and said fired configuration; and a cutting memberconfigured to transect said mount portion from said compressible layer,wherein said cutting member is actuatable by said firing sled when saidfiring sled approaches said distal end.